diff --git a/sc/qa/unit/subsequent_filters-test.cxx b/sc/qa/unit/subsequent_filters-test.cxx
index 1fdec5f26079..86a67c2cea91 100644
--- a/sc/qa/unit/subsequent_filters-test.cxx
+++ b/sc/qa/unit/subsequent_filters-test.cxx
@@ -3932,6 +3932,13 @@ void ScFiltersTest::testTdf97598XLSX()
 #ifdef UNX
 void ScFiltersTest::testUnicodeFileNameGnumeric()
 {
+    // Mapping the LO-interal URL
+    // <file:///.../sc/qa/unit/data/gnumeric/t%C3%A4%C3%9Ft.gnumeric> to the
+    // repo's file sc/qa/unit/data/gnumeric/t\303\244\303\237t.gnumeric only
+    // works when the system encoding is UTF-8:
+    if (osl_getThreadTextEncoding() != RTL_TEXTENCODING_UTF8) {
+        return;
+    }
     OString aFileNamePrefix= "t" + OString(RTL_CONSTASCII_STRINGPARAM("\u00e4\u00df")) + "t.";
     ScDocShellRef xDocSh = loadDoc(OStringToOUString(aFileNamePrefix, RTL_TEXTENCODING_UTF8), FORMAT_GNUMERIC);
     CPPUNIT_ASSERT(xDocSh.is());