diff --git a/icu4c/source/test/intltest/messageformat2test.cpp b/icu4c/source/test/intltest/messageformat2test.cpp
index 524ee4ab79d9..48b6811dd853 100644
--- a/icu4c/source/test/intltest/messageformat2test.cpp
+++ b/icu4c/source/test/intltest/messageformat2test.cpp
@@ -30,6 +30,8 @@ TestMessageFormat2::runIndexedTest(int32_t index, UBool exec,
     TESTCASE_AUTO(testAPI);
     TESTCASE_AUTO(testAPISimple);
     TESTCASE_AUTO(testDataModelAPI);
+    TESTCASE_AUTO(testHighLoneSurrogate);
+    TESTCASE_AUTO(testLowLoneSurrogate);
     TESTCASE_AUTO(dataDrivenTests);
     TESTCASE_AUTO_END;
 }
@@ -263,6 +265,30 @@ void TestMessageFormat2::testAPICustomFunctions() {
     delete person;
 }
 
+// ICU-22890 lone surrogate cause infinity loop
+void TestMessageFormat2::testHighLoneSurrogate() {
+    IcuTestErrorCode errorCode(*this, "testHighLoneSurrogate");
+    UParseError pe = { 0, 0, {0}, {0} };
+    // Lone surrogate with only high surrogate
+    UnicodeString loneSurrogate({0xda02, 0});
+    icu::message2::MessageFormatter msgfmt1 =
+      icu::message2::MessageFormatter::Builder(errorCode)
+      .setPattern(loneSurrogate, pe, errorCode)
+      .build(errorCode);
+}
+
+// ICU-22890 lone surrogate cause infinity loop
+void TestMessageFormat2::testLowLoneSurrogate() {
+    IcuTestErrorCode errorCode(*this, "testLowLoneSurrogate");
+    UParseError pe = { 0, 0, {0}, {0} };
+    // Lone surrogate with only low surrogate
+    UnicodeString loneSurrogate({0xdc02, 0});
+    icu::message2::MessageFormatter msgfmt2 =
+      icu::message2::MessageFormatter::Builder(errorCode)
+      .setPattern(loneSurrogate, pe, errorCode)
+      .build(errorCode);
+}
+
 void TestMessageFormat2::dataDrivenTests() {
     IcuTestErrorCode errorCode(*this, "jsonTests");
 
diff --git a/icu4c/source/test/intltest/messageformat2test.h b/icu4c/source/test/intltest/messageformat2test.h
index 7c7c2612f50d..b4b250cb5106 100644
--- a/icu4c/source/test/intltest/messageformat2test.h
+++ b/icu4c/source/test/intltest/messageformat2test.h
@@ -87,6 +87,8 @@ class TestMessageFormat2: public IntlTest {
     void testMessageFormatDateTimeSkeleton(message2::TestCase::Builder&, IcuTestErrorCode&);
     void testMf1Behavior(message2::TestCase::Builder&, IcuTestErrorCode&);
 
+    void testHighLoneSurrogate(void);
+    void testLowLoneSurrogate(void);
 }; // class TestMessageFormat2
 
 U_NAMESPACE_BEGIN