diff --git a/Appendix E/9251.cpp b/Appendix E/9251.cpp
new file mode 100644
index 00000000..c11aaab5
--- /dev/null
+++ b/Appendix E/9251.cpp	
@@ -0,0 +1,25 @@
+// http://boj.kr/cf49db3b3f394eb192a482da5f7a8f84
+#include <bits/stdc++.h>
+using namespace std;
+
+string a, b;
+int n, m;
+int d[1005][1005];
+
+int main() {
+  ios::sync_with_stdio(0);
+  cin.tie(0);
+
+  cin >> a >> b;
+  n = a.size();
+  m = b.size();
+
+  for(int i = 1; i <= n; i++){
+    for(int j = 1; j <= m; j++){
+      if(a[i-1] == b[j-1])
+        d[i][j] = d[i-1][j-1] + 1;
+      d[i][j] = max({d[i][j], d[i-1][j], d[i][j-1]});
+    }
+  }
+  cout << d[n][m];
+}