diff --git a/icu4c/source/test/testdata/icuio.txt b/icu4c/source/test/testdata/icuio.txt
index 70d598bba3..92c4f012ee 100644
--- a/icu4c/source/test/testdata/icuio.txt
+++ b/icu4c/source/test/testdata/icuio.txt
@@ -142,6 +142,45 @@ icuio {
                 {
                     "%e", "1.200000e+000", "d", "1.2"
                 }
+                {
+                    "%*e%e", "1.200000e+000 4.825000e+000", "d", "4.825"
+                }
+                {
+                    "%C", "1234", "2", "31"
+                }
+                {
+                    "%*C%C", "1234", "2", "32"
+                }
+                {
+                    "%S", "1234 5678", "S", "1234"
+                }
+                {
+                    "%*S%S", "1234 5678", "S", "5678"
+                }
+                {
+                    "%d", "1234 5678", "4", "4D2"
+                }
+                {
+                    "%*d%d", "1234 5678", "4", "162E"
+                }
+                {
+                    "%hd", "1234 5678", "2", "4D2"
+                }
+                {
+                    "%*hd%hd", "1234 5678", "2", "162E"
+                }
+                {
+                    "%x", "abcd ef01", "4", "abcd"
+                }
+                {
+                    "%*hx%hx", "abcd ef01", "4", "ef01"
+                }
+                {
+                    "%[abce]", "abcd ef01", "S", "abc"
+                }
+                {
+                    "%*[abce]%[de\ ]", "abcd ef01", "S", "d e"
+                }
             }
         }
     }