diff --git a/src/testdir/test_substitute.vim b/src/testdir/test_substitute.vim
index 32e2f27..73e6bef 100644
--- a/src/testdir/test_substitute.vim
+++ b/src/testdir/test_substitute.vim
@@ -1415,18 +1415,19 @@
 endfunc
 
 " Check handling expanding "~" resulting in extremely long text.
-func Test_substitute_tilde_too_long()
-  enew!
-
-  s/.*/ixxx
-  s//~~~~~~~~~AAAAAAA@(
-
-  " Either fails with "out of memory" or "text too long".
-  " This can take a long time.
-  call assert_fails('sil! norm &&&&&&&&&', ['E1240:\|E342:'])
-
-  bwipe!
-endfunc
+" FIXME: disabled, it takes too long to run on CI
+#func Test_substitute_tilde_too_long()
+#  enew!
+#
+#  s/.*/ixxx
+#  s//~~~~~~~~~AAAAAAA@(
+#
+#  " Either fails with "out of memory" or "text too long".
+#  " This can take a long time.
+#  call assert_fails('sil! norm &&&&&&&&&', ['E1240:\|E342:'])
+#
+#  bwipe!
+#endfunc
 
 " This should be done last to reveal a memory leak when vim_regsub_both() is
 " called to evaluate an expression but it is not used in a second call.