diff --git a/dox/resources/occt_ug_html.doxyfile b/dox/resources/occt_ug_html.doxyfile
index a3a577261f..267e6a9de1 100644
--- a/dox/resources/occt_ug_html.doxyfile
+++ b/dox/resources/occt_ug_html.doxyfile
@@ -21,7 +21,6 @@ FILE_PATTERNS          = *.md *.dox
 RECURSIVE              = YES
 SOURCE_BROWSER         = NO
 INLINE_SOURCES         = YES
-COLS_IN_ALPHA_INDEX    = 5
 GENERATE_DOCSET        = NO
 GENERATE_CHI           = NO
 GENERATE_QHP           = NO
diff --git a/dox/resources/occt_ug_pdf.doxyfile b/dox/resources/occt_ug_pdf.doxyfile
index 3d30948423..8457345812 100644
--- a/dox/resources/occt_ug_pdf.doxyfile
+++ b/dox/resources/occt_ug_pdf.doxyfile
@@ -21,7 +21,6 @@ FILE_PATTERNS          = *.md *.dox
 RECURSIVE              = YES
 SOURCE_BROWSER         = NO
 INLINE_SOURCES         = YES
-COLS_IN_ALPHA_INDEX    = 5
 GENERATE_DOCSET        = NO
 GENERATE_CHI           = NO
 GENERATE_QHP           = NO