diff --git a/include/ustring.h b/include/ustring.h
index 293a579..7ae2c1b 100644
--- a/include/ustring.h
+++ b/include/ustring.h
@@ -355,6 +355,19 @@ UString ustring_join(UString const *strings, ulib_uint count, UString sep);
 ULIB_API
 UString ustring_repeating(UString string, ulib_uint times);
 
+/**
+ * Returns a new string obtained by replacing all occurrences of a character with another.
+ *
+ * @param string String.
+ * @param needle Character to replace.
+ * @param replacement Replacement character.
+ * @return New string.
+ *
+ * @destructor{ustring_deinit}
+ */
+ULIB_API
+UString ustring_replacing_char(UString string, char needle, char replacement);
+
 /**
  * Checks if the string does not contain lowercase characters.
  *
diff --git a/src/ustring.c b/src/ustring.c
index ca7cee3..8845e97 100644
--- a/src/ustring.c
+++ b/src/ustring.c
@@ -290,6 +290,18 @@ UString ustring_repeating(UString string, ulib_uint times) {
     return ret;
 }
 
+UString ustring_replacing_char(UString string, char needle, char replacement) {
+    ulib_uint const len = ustring_length(string);
+    UString ret;
+    char *buf = ustring(&ret, len);
+    if (!len) return ret;
+    memcpy(buf, ustring_data(string), len);
+    for (char *cur = buf; (cur = memchr(cur, needle, len - (cur - buf))) != NULL; ++cur) {
+        *cur = replacement;
+    }
+    return ret;
+}
+
 UString ustring_to_upper(UString string) {
     UString ret;
     ulib_uint const len = ustring_length(string);
diff --git a/test/tests/ustring_tests.c b/test/tests/ustring_tests.c
index 03734d6..0d7cb38 100644
--- a/test/tests/ustring_tests.c
+++ b/test/tests/ustring_tests.c
@@ -202,7 +202,10 @@ bool ustring_test_base(void) {
 
     a = ustring_repeating(ustring_literal("123"), 4);
     utest_assert_ustring(a, ==, ustring_literal("123123123123"));
+    b = ustring_replacing_char(a, '3', '4');
+    utest_assert_ustring(b, ==, ustring_literal("124124124124"));
     ustring_deinit(&a);
+    ustring_deinit(&b);
 
     a = ustring_with_format("%d%d%d", 1, 2, 3);
     utest_assert_ustring(a, ==, ustring_literal("123"));