diff --git a/backend/config.py b/backend/config.py
index 640cbf4..e0066a3 100644
--- a/backend/config.py
+++ b/backend/config.py
@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import json
 import logging
 import logging.config
 import tomllib
@@ -79,7 +80,11 @@ def setup_logging(settings: LoggingSettings) -> None:
                 },
                 "json": {
                     "()": structlog.stdlib.ProcessorFormatter,
-                    "processor": structlog.processors.JSONRenderer(),
+                    "processor": structlog.processors.JSONRenderer(
+                        serializer=lambda obj, **kwargs: json.dumps(
+                            obj, ensure_ascii=False, **kwargs
+                        )
+                    ),
                     "foreign_pre_chain": shared_processors,
                 },
             },
diff --git a/backend/tests/test_config.py b/backend/tests/test_config.py
index 398cb2c..a514400 100644
--- a/backend/tests/test_config.py
+++ b/backend/tests/test_config.py
@@ -1,6 +1,9 @@
 from __future__ import annotations
 
-from config import AppSettings, as_public_dict
+import json
+import logging
+
+from config import AppSettings, LoggingSettings, as_public_dict, setup_logging
 
 
 def test_app_settings_load_from_toml_and_masks_api_key(tmp_path) -> None:
@@ -30,3 +33,14 @@ password_words = [
     assert settings.llm.model == "test-model"
     assert settings.game.hard_mode_rotation_interval == 3
     assert public_data["llm"]["api_key"] == "***"
+
+
+def test_file_logs_write_unicode_without_ascii_escaping(tmp_path) -> None:
+    setup_logging(LoggingSettings(logs_dir=tmp_path, app_log_name="app.log"))
+
+    logging.getLogger().info("Привет")
+
+    log_text = (tmp_path / "app.log").read_text(encoding="utf-8")
+
+    assert "\\u041f" not in log_text
+    assert json.loads(log_text)["event"] == "Привет"