diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8deff64..0112358 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -66,6 +66,7 @@ add_executable(App ./src/main.cpp
         src/endpoints_handlers/GetUserTreatmentSchemeExecutor.h
         src/endpoints_handlers/GetDiariesExecutor.h
         src/endpoints_handlers/PostDiaryExecutor.h
+        src/endpoints_handlers/PutDiaryExecutor.h
         src/DAO/IDiariesDAO.h
         src/dtos/diary_dto.h
         src/DAO/MySQLDiariesDao.cpp
diff --git a/src/DAO/IDiariesDAO.h b/src/DAO/IDiariesDAO.h
index d68a6ca..8c27c8d 100644
--- a/src/DAO/IDiariesDAO.h
+++ b/src/DAO/IDiariesDAO.h
@@ -17,6 +17,12 @@ public:
     const diary_dto& dto
   ) const = 0;
 
+  virtual void UpdateDiary(
+    const std::string& user_uuid,
+    const std::string& diary_uuid,
+    const diary_dto& dto
+  ) const = 0;
+
   virtual ~IDiariesDAO() = default;
 };
 }
diff --git a/src/DAO/MySQLDiariesDAO.cpp b/src/DAO/MySQLDiariesDAO.cpp
index a489c76..c935411 100644
--- a/src/DAO/MySQLDiariesDAO.cpp
+++ b/src/DAO/MySQLDiariesDAO.cpp
@@ -1,5 +1,7 @@
 #include "MySQLDiariesDAO.h"
 
+#include "../exceptions/session_exception.h"
+
 namespace uad
 {
 MySqlDiariesDAO::MySqlDiariesDAO(mysqlx::Session& session) : session_(session)
@@ -107,4 +109,44 @@ void MySqlDiariesDAO::СreateDiary(const std::string& user_uuid, const diary_dto
 
   stmt.execute();
 }
+
+void MySqlDiariesDAO::UpdateDiary(
+  const std::string& user_uuid,
+  const std::string& diary_uuid,
+  const diary_dto& dto) const
+{
+  auto stmt = session_.sql(R"(
+        UPDATE `up_and_down`.`diaries`
+        SET
+            mania_level = ?,
+            depression_level = ?,
+            mood_level = ?,
+            activity_level = ?,
+            appetite_level = ?,
+            dream_level = ?,
+            anxiety_level = ?,
+            comment = ?,
+            user_treatment_schemes_uuid = ?
+        WHERE uuid = ?
+    )");
+
+  stmt.bind(
+      dto.mania_level,
+      dto.depression_level,
+      dto.mood_level,
+      dto.activity_level,
+      dto.appetite_level,
+      dto.dream_level,
+      dto.anxiety_level,
+      dto.comment,
+      dto.user_treatment_scheme_uuid,
+      dto.uuid
+  );
+
+  auto res = stmt.execute();
+
+  if (res.getAffectedItemsCount() == 0) {
+    throw session_exception(boost::beast::http::status::not_found, "Diary not found");
+  }
+}
 }
diff --git a/src/DAO/MySQLDiariesDAO.h b/src/DAO/MySQLDiariesDAO.h
index 6097898..660712f 100644
--- a/src/DAO/MySQLDiariesDAO.h
+++ b/src/DAO/MySQLDiariesDAO.h
@@ -21,5 +21,11 @@ public:
     const std::string& user_uuid,
     const diary_dto& dto
   ) const override;
+
+  void UpdateDiary(
+    const std::string& user_uuid,
+    const std::string& diary_uuid,
+    const diary_dto& dto
+  ) const override;
 };
 }
diff --git a/src/endpoints_handlers/PostDiaryExecutor.h b/src/endpoints_handlers/PostDiaryExecutor.h
index c4b9080..bc6d9f7 100644
--- a/src/endpoints_handlers/PostDiaryExecutor.h
+++ b/src/endpoints_handlers/PostDiaryExecutor.h
@@ -71,7 +71,7 @@ public:
 
     diary_dto dto;
 
-    dto.uuid = obj["uuid"].as_string().c_str();
+    dto.uuid = GenerateUUID();
     dto.time_ms = obj["time_ms"].as_int64();
     dto.mania_level = obj["mania_level"].as_int64();
     dto.depression_level = obj["depression_level"].as_int64();
@@ -80,13 +80,9 @@ public:
     dto.appetite_level = obj["appetite_level"].as_int64();
     dto.dream_level = obj["dream_level"].as_int64();
     dto.anxiety_level = obj["anxiety_level"].as_int64();
-
-    if (obj.contains("comment"))
-      dto.comment = obj["comment"].as_string().c_str();
-
-    if (obj.contains("user_treatment_scheme_uuid"))
-      dto.user_treatment_scheme_uuid =
-        obj["user_treatment_scheme_uuid"].as_string().c_str();
+    dto.comment = obj["comment"].as_string().c_str();
+    dto.user_treatment_scheme_uuid =
+      obj["user_treatment_scheme_uuid"].as_string().c_str();
 
     try
     {
diff --git a/src/endpoints_handlers/PutDiaryExecutor.h b/src/endpoints_handlers/PutDiaryExecutor.h
new file mode 100644
index 0000000..068c8d3
--- /dev/null
+++ b/src/endpoints_handlers/PutDiaryExecutor.h
@@ -0,0 +1,119 @@
+#pragma once
+#include <boost/log/trivial.hpp>
+
+#include <regex>
+#include <boost/json.hpp>
+#include <boost/mpl/vector/vector0.hpp>
+#include <mysqlx/xdevapi.h>
+
+#include "IExecutor.h"
+#include "../DAO/IAuthDAO.h"
+#include "../DAO/IDiariesDAO.h"
+#include "../DAO/IUserTreatmentSchemesDAO.h"
+#include "../exceptions/session_exception.h"
+
+namespace uad
+{
+template <class Body, class Allocator, class ResponseType>
+class PutDiaryExecutor
+{
+  mysqlx::Session& session_;
+  const std::shared_ptr<IAuthDAO>& auth_dao_;
+  const std::shared_ptr<IDiariesDAO>& diaries_dao_;
+
+public:
+  PutDiaryExecutor(
+    mysqlx::Session& session,
+    const std::shared_ptr<IAuthDAO>& auth_dao,
+    const std::shared_ptr<IDiariesDAO>& diaries_dao
+  ) : session_(session), auth_dao_(auth_dao), diaries_dao_(diaries_dao)
+  {
+  }
+
+  [[nodiscard]] boost::beast::http::response<ResponseType> operator ()(
+    boost::beast::http::request<Body, boost::beast::http::basic_fields<Allocator>>&& req,
+    std::string diary_uuid
+  )
+  {
+    using namespace boost;
+    using namespace boost::json;
+    using namespace boost::beast;
+    using namespace std::string_literals;
+    using namespace std::string_view_literals;
+
+    constexpr std::string_view auth_prefix = "Bearer "sv;
+    static const std::string invalid_token_message =
+      "PUT /api/v1/Diary - Response 401: Unauthorized"s;
+
+    BOOST_LOG_TRIVIAL(info) << "PUT /api/v1/Diary - Request";
+
+    if (req[http::field::authorization].size() <= auth_prefix.size())
+    {
+      BOOST_LOG_TRIVIAL(error) << invalid_token_message;
+      throw session_exception(http::status::unauthorized, "Unauthorized");
+    }
+
+    const std::string auth_token = {
+        req[http::field::authorization].begin() + auth_prefix.size(),
+        req[http::field::authorization].end()
+      };
+
+    if (!auth_dao_->HasAuthorized(auth_token))
+    {
+      BOOST_LOG_TRIVIAL(error) << invalid_token_message;
+      throw session_exception(http::status::unauthorized, "Unauthorized");
+    }
+
+    std::string_view user_uuid_ref = auth_dao_->GetUUID(auth_token);
+    const std::string user_uuid{user_uuid_ref.begin(), user_uuid_ref.end()};
+
+    value val = json::parse(req.body());
+    object& obj = val.as_object();
+
+    diary_dto dto;
+
+    dto.uuid = diary_uuid;
+    dto.mania_level = obj["mania_level"].as_int64();
+    dto.depression_level = obj["depression_level"].as_int64();
+    dto.mood_level = obj["mood_level"].as_int64();
+    dto.activity_level = obj["activity_level"].as_int64();
+    dto.appetite_level = obj["appetite_level"].as_int64();
+    dto.dream_level = obj["dream_level"].as_int64();
+    dto.anxiety_level = obj["anxiety_level"].as_int64();
+    dto.comment = obj["comment"].as_string().c_str();
+    dto.user_treatment_scheme_uuid = obj["user_treatment_scheme_uuid"].as_string().c_str();
+
+    diaries_dao_->UpdateDiary(user_uuid, diary_uuid, dto);
+
+    http::response<ResponseType> res{http::status::ok, req.version()};
+    value response_body = ToJSON(dto);
+
+    res.body() = serialize(response_body);
+    res.set(http::field::content_type, "application/json");
+    res.content_length(res.body().size());
+
+    return res;
+  }
+
+private:
+  boost::json::object ToJSON(const diary_dto& diary)
+  {
+    boost::json::object diary_json;
+
+    diary_json["uuid"] = diary.uuid;
+    diary_json["time"] = diary.time_ms;
+    diary_json["mania_level"] = diary.mania_level;
+    diary_json["depression_level"] = diary.depression_level;
+    diary_json["mood_level"] = diary.mood_level;
+    diary_json["activity_level"] = diary.activity_level;
+    diary_json["appetite_level"] = diary.appetite_level;
+    diary_json["dream_level"] = diary.dream_level;
+    diary_json["anxiety_level"] = diary.anxiety_level;
+    diary_json["comment"] = diary.comment;
+    diary_json["user_treatment_scheme_uuid"] =
+      diary.user_treatment_scheme_uuid;
+
+    return diary_json;
+  }
+};
+}
diff --git a/src/endpoints_handlers/RootExecutor.h b/src/endpoints_handlers/RootExecutor.h
index 6710075..7ad6db7 100644
--- a/src/endpoints_handlers/RootExecutor.h
+++ b/src/endpoints_handlers/RootExecutor.h
@@ -16,6 +16,7 @@
 #include "PostUserMedicationsExecutor.h"
 #include "GetDiariesExecutor.h"
 #include "PostDiaryExecutor.h"
+#include "PutDiaryExecutor.h"
 #include "../DAO/IUserDAO.h"
 #include "../DAO/IAuthDAO.h"
 #include "../DAO/IDiariesDAO.h"
@@ -48,6 +49,8 @@ class RootExecutor
     Body, Allocator, boost::beast::http::string_body>;
   using RoutePostDiaryExecutor = PostDiaryExecutor<
     Body, Allocator, boost::beast::http::string_body>;
+  using RoutePutDiaryExecutor = PutDiaryExecutor<
+    Body, Allocator, boost::beast::http::string_body>;
   using IRouteController = IController<Body, Allocator, boost::beast::http::string_body>;
   using RouteController = Controller<Body, Allocator, boost::beast::http::string_body>;
   using RoutesPathes = std::unordered_map<std::string, std::unique_ptr<IRouteController>>;
@@ -203,7 +206,11 @@ public:
 
       if (req.method() == boost::beast::http::verb::put)
       {
-
+        return send(PutDiaryExecutor<Body, Allocator, ResponseType>(
+          session_,
+          auth_dao_,
+          diaries_dao_
+          )(std::move(req), uuid));
       }
     }