diff --git a/docs/build_mozc_in_osx.md b/docs/build_mozc_in_osx.md
index fa3ff1c1ed..1d57542cd8 100644
--- a/docs/build_mozc_in_osx.md
+++ b/docs/build_mozc_in_osx.md
@@ -71,7 +71,7 @@ python build_tools/update_deps.py
 In this step, additional build dependencies will be downloaded.
 
   * [Ninja 1.11.0](https://github.com/ninja-build/ninja/releases/download/v1.11.0/ninja-mac.zip)
-  * [Qt 6.5.2](https://download.qt.io/archive/qt/6.5/6.5.2/submodules/qtbase-everywhere-src-6.5.2.tar.xz)
+  * [Qt 6.6.0](https://download.qt.io/archive/qt/6.6/6.6.0/submodules/qtbase-everywhere-src-6.6.0.tar.xz)
   * [git submodules](../.gitmodules)
 
 You can specify `--noqt` option if you would like to use your own Qt binaries.
diff --git a/docs/build_mozc_in_windows.md b/docs/build_mozc_in_windows.md
index b088f5e85c..814f2480fd 100644
--- a/docs/build_mozc_in_windows.md
+++ b/docs/build_mozc_in_windows.md
@@ -67,7 +67,7 @@ python build_tools/update_deps.py
 In this step, additional build dependencies will be downloaded.
 
   * [Ninja 1.11.0](https://github.com/ninja-build/ninja/releases/download/v1.11.0/ninja-win.zip)
-  * [Qt 6.5.2](https://download.qt.io/archive/qt/6.5/6.5.2/submodules/qtbase-everywhere-src-6.5.2.tar.xz)
+  * [Qt 6.6.0](https://download.qt.io/archive/qt/6.6/6.6.0/submodules/qtbase-everywhere-src-6.6.0.tar.xz)
   * [WiX 3.14.0.6526](https://wixtoolset.org/downloads/v3.14.0.6526/wix314-binaries.zip)
   * [git submodules](../.gitmodules)
 
diff --git a/src/build_tools/build_qt.py b/src/build_tools/build_qt.py
index f893699dba..d169d706e9 100755
--- a/src/build_tools/build_qt.py
+++ b/src/build_tools/build_qt.py
@@ -37,7 +37,7 @@
 
 By default, this script assumes that Qt archives are stored as
 
-  src/third_party_cache/qtbase-everywhere-src-6.5.3.tar.xz
+  src/third_party_cache/qtbase-everywhere-src-6.6.0.tar.xz
 
 and Qt src files that are necessary to build Mozc will be checked out into
 
@@ -69,7 +69,7 @@
 ABS_QT_DEST_DIR = ABS_MOZC_SRC_DIR.joinpath('third_party', 'qt')
 # The archive filename should be consistent with update_deps.py.
 ABS_QT6_ARCHIVE_PATH = ABS_MOZC_SRC_DIR.joinpath(
-    'third_party_cache', 'qtbase-everywhere-src-6.5.3.tar.xz')
+    'third_party_cache', 'qtbase-everywhere-src-6.6.0.tar.xz')
 ABS_DEFAULT_NINJA_DIR = ABS_MOZC_SRC_DIR.joinpath('third_party', 'ninja')
 
 
@@ -296,7 +296,6 @@ def make_configure_options(args: argparse.Namespace) -> list[str]:
                           '-no-feature-sqlmodel',
                           '-no-feature-sspi',
                           '-no-feature-stringlistmodel',
-                          '-no-feature-systemsemaphore',
                           '-no-feature-tabletevent',
                           '-no-feature-testlib',
                           '-no-feature-textbrowser',