diff --git a/src/pytest_html/html_report.py b/src/pytest_html/html_report.py
index 045c52c1..75528a57 100644
--- a/src/pytest_html/html_report.py
+++ b/src/pytest_html/html_report.py
@@ -256,10 +256,10 @@ def _save_report(self, report_content):
         if not self.self_contained:
             assets_dir.mkdir(parents=True, exist_ok=True)
 
-        self.logfile.write_text(report_content)
+        self.logfile.write_text(report_content, encoding="utf-8")
         if not self.self_contained:
             style_path = assets_dir / "style.css"
-            style_path.write_text(self.style_css)
+            style_path.write_text(self.style_css, encoding="utf-8")
 
     def _post_process_reports(self):
         for test_name, test_reports in self.reports.items():