diff --git a/src/genesis/writer/template_mapper.py b/src/genesis/writer/template_mapper.py
index 436879d..abee43f 100644
--- a/src/genesis/writer/template_mapper.py
+++ b/src/genesis/writer/template_mapper.py
@@ -1,22 +1,36 @@
-"""模板 → 有序章节规格映射（Phase 5）。"""
+"""模板 → 有序章节规格映射（Phase 5）。
+
+真实 ParsedTemplate.sections 为 ChapterMarker 列表；章节由 type=="heading" 起，
+紧随其后的 type=="placeholder" 且形如 `section:<id>` 的标记归属该章，
+用于确定 chapter_id 与 section_placeholder（语言无关、按文档顺序）。
+"""
 from __future__ import annotations
 
+import re
+
+from genesis.data_models import ParsedTemplate
 from genesis.writer.models import ChapterSpec
 
+_SECTION_RE = re.compile(r"^section:(.+)$")
 
-def map_template(parsed) -> list[ChapterSpec]:
-    """按模板 Heading 层级顺序产出有序章节列表。
 
-    `parsed.chapters` 为 WordTemplateParser 产出的章节标记列表，
-    每项含 chapter_id / title / section_placeholder 属性。
-    """
+def map_template(parsed: ParsedTemplate) -> list[ChapterSpec]:
     specs: list[ChapterSpec] = []
-    for ch in getattr(parsed, "chapters", []):
-        specs.append(
-            ChapterSpec(
-                chapter_id=getattr(ch, "chapter_id", ""),
-                title=getattr(ch, "title", ""),
-                section_placeholder=getattr(ch, "section_placeholder", None),
+    idx = 0
+    current: ChapterSpec | None = None
+    for ch in getattr(parsed, "sections", []):
+        t = getattr(ch, "type", None)
+        if t == "heading":
+            idx += 1
+            current = ChapterSpec(
+                chapter_id=f"chapter_{idx}", title=getattr(ch, "name", ""), section_placeholder=None
             )
-        )
+            specs.append(current)
+        elif t == "placeholder" and current is not None:
+            m = _SECTION_RE.match(getattr(ch, "name", ""))
+            if m:
+                sid = m.group(1)
+                current.section_placeholder = getattr(ch, "name", "")
+                if current.chapter_id.startswith("chapter_"):
+                    current.chapter_id = sid
     return specs
diff --git a/tests/test_phase5_template_mapper.py b/tests/test_phase5_template_mapper.py
index 001e160..d40b38a 100644
--- a/tests/test_phase5_template_mapper.py
+++ b/tests/test_phase5_template_mapper.py
@@ -1,17 +1,32 @@
-from types import SimpleNamespace
-from genesis.writer.template_mapper import map_template
+from genesis.data_models import ChapterMarker, ParsedTemplate
 from genesis.writer.models import ChapterSpec
+from genesis.writer.template_mapper import map_template
 
 
-def _fake_parsed():
-    ch1 = SimpleNamespace(chapter_id="intro", title="はじめに", section_placeholder="{{section:introduction}}")
-    ch2 = SimpleNamespace(chapter_id="db_design", title="DB 設計", section_placeholder=None)
-    return SimpleNamespace(chapters=[ch1, ch2])
+def _parsed():
+    sections = [
+        ChapterMarker(type="heading", name="はじめに", level=1),
+        ChapterMarker(type="placeholder", name="section:introduction", level=0),
+        ChapterMarker(type="heading", name="DB 設計", level=1),
+        ChapterMarker(type="placeholder", name="section:db_design", level=0),
+        ChapterMarker(type="bookmark", name="bm1", level=0),
+    ]
+    return ParsedTemplate(file_name="t.docx", sections=sections, placeholders={"section:introduction": "x"}, styles={})
 
 
-def test_map_template_ordered():
-    specs = map_template(_fake_parsed())
-    assert [s.chapter_id for s in specs] == ["intro", "db_design"]
-    assert specs[0].section_placeholder == "{{section:introduction}}"
-    assert specs[1].section_placeholder is None
+def test_map_template_ordered_and_assigns_ids():
+    specs = map_template(_parsed())
+    assert [s.title for s in specs] == ["はじめに", "DB 設計"]
+    assert specs[0].chapter_id == "introduction"
+    assert specs[0].section_placeholder == "section:introduction"
+    assert specs[1].chapter_id == "db_design"
+    assert specs[1].section_placeholder == "section:db_design"
     assert all(isinstance(s, ChapterSpec) for s in specs)
+
+
+def test_map_template_falls_back_without_placeholder():
+    sections = [ChapterMarker(type="heading", name="附録", level=1)]
+    parsed = ParsedTemplate(file_name="t.docx", sections=sections, placeholders={}, styles={})
+    specs = map_template(parsed)
+    assert specs[0].chapter_id == "chapter_1"
+    assert specs[0].section_placeholder is None