diff --git a/函数判断素数.c b/函数判断素数.c
new file mode 100644
index 0000000..e50fe97
--- /dev/null
+++ b/函数判断素数.c
@@ -0,0 +1,39 @@
+#include<stdio.h>
+#include<math.h>
+int judge(int m)
+{
+	int i,count=0;
+	if(m<2)
+	{
+		return 0;
+	}
+	for(i=2;i<=sqrt(m);i++)
+	{
+		if(m%i==0)
+		{
+			count++;
+		}
+	}
+	if(count==0)
+	{
+		return 1;
+	}
+	else
+	{
+		return 0;
+	}
+}
+int main()
+{
+	int n;
+	scanf("%d",&n);
+	if(judge(n)==1)
+	{
+		printf("Yes");
+	}
+	else
+	{
+		printf("No");
+	}
+	return 0;
+}