diff --git a/arrays_and_strings/is_isomorphic.py b/arrays_and_strings/is_isomorphic.py
new file mode 100644
index 0000000..badd2ab
--- /dev/null
+++ b/arrays_and_strings/is_isomorphic.py
@@ -0,0 +1,15 @@
+def is_isomorphic(s: str, t: str) -> bool:
+        
+        map_s_to_t = {}
+        map_t_to_s = {}
+        
+        for ss, tt in zip(s, t):
+            
+            if (ss not in map_s_to_t) and (tt not in map_t_to_s):
+                map_s_to_t[ss] = tt
+                map_t_to_s[tt] = ss
+            
+            elif (map_s_to_t.get(ss) != tt) or (map_t_to_s.get(tt) != ss):
+                return False
+
+        return True