diff --git a/src/main/java/leet/book/queueStack/NumIslands.java b/src/main/java/leet/book/queueStack/NumIslands.java
new file mode 100644
index 0000000..2970847
--- /dev/null
+++ b/src/main/java/leet/book/queueStack/NumIslands.java
@@ -0,0 +1,35 @@
+package leet.book.queueStack;
+
+/**
+ * Created with IntelliJ IDEA.
+ *
+ * @author: 轩辕龙儿
+ * @date: 2021/7/2 10:53
+ * @Description: No Description
+ */
+public class NumIslands {
+    class Solution {
+        public int numIslands(char[][] grid) {
+            int count = 0;
+            for(int i = 0; i < grid.length; i++) {
+                for(int j = 0; j < grid[0].length; j++) {
+                    if(grid[i][j] == '1'){
+                        dfs(grid, i, j);
+                        count++;
+                    }
+                }
+            }
+            return count;
+        }
+        private void dfs(char[][] grid, int x, int y){
+            if(x < 0 || y < 0 || x >= grid.length || y >= grid[0].length || grid[x][y] == '0') {
+                return;
+            }
+            grid[x][y] = '0';
+            dfs(grid, x + 1, y);
+            dfs(grid, x, y + 1);
+            dfs(grid, x - 1, y);
+            dfs(grid, x, y - 1);
+        }
+    }
+}