diff --git a/sm3/sm3blocks_test.go b/sm3/sm3blocks_test.go
index c5fca6d..b613f01 100644
--- a/sm3/sm3blocks_test.go
+++ b/sm3/sm3blocks_test.go
@@ -7,6 +7,7 @@
 package sm3
 
 import (
+	"bytes"
 	"encoding/binary"
 	"fmt"
 	"testing"
@@ -34,6 +35,24 @@ func createOneBlockBy4() [4]*byte {
 	return [4]*byte{&p1[0], &p2[0], &p3[0], &p4[0]}
 }
 
+func createOneRandomBlockBy4() [4]*byte {
+	var p1 = [64]byte{
+		0x49, 0xcf, 0x14, 0x64, 0x9f, 0x32, 0x4a, 0x07,
+		0xe0, 0xd5, 0xbb, 0x2a, 0x00, 0xf7, 0xf0, 0x5d,
+		0x5f, 0x5b, 0xdd, 0x6d, 0x14, 0xdf, 0xf0, 0x28,
+		0xe0, 0x71, 0x32, 0x7e, 0xc0, 0x31, 0x10, 0x45,
+		0x90, 0xed, 0xdb, 0x18, 0xf9, 0x8b, 0x76, 0x3e,
+		0x18, 0xbf, 0x38, 0x2f, 0xf7, 0xc3, 0x87, 0x5f,
+		0x30, 0x27, 0x7f, 0x31, 0x79, 0xba, 0xeb, 0xd7,
+		0x95, 0xe7, 0x85, 0x3f, 0xa6, 0x43, 0xfd, 0xf2,
+	}
+
+	var p2 = p1
+	var p3 = p1
+	var p4 = p1
+	return [4]*byte{&p1[0], &p2[0], &p3[0], &p4[0]}
+}
+
 func createTwoBlocksBy4() [4]*byte {
 	var p1 [128]byte
 	p1[0] = 0x61
@@ -65,6 +84,17 @@ func TestBlockMultBy4(t *testing.T) {
 		}
 	}
 
+	digs = initState4()
+	p = createOneRandomBlockBy4()
+	blockMultBy4(&digs[0], &p[0], &buffer[0], 1)
+	expected = "[8c2b6dd5 cc894103 6ec67d69 6154d5fd 62f48fd 984112e3 9e63659e 542709af]"
+	for i := 0; i < 4; i++ {
+		s := fmt.Sprintf("%x", digs[i][:])
+		if s != expected {
+			t.Errorf("digs[%d] got %s", i, s)
+		}
+	}
+
 	digs = initState4()
 	p = createTwoBlocksBy4()
 	blockMultBy4(&digs[0], &p[0], &buffer[0], 2)
@@ -85,9 +115,7 @@ func TestCopyResultsBy4(t *testing.T) {
 		for j := 0; j < 8; j++ {
 			m[i][j] = k
 			k++
-			fmt.Printf("%08x ", m[i][j])
 		}
-		fmt.Println()
 	}
 	copyResultsBy4(&m[0][0], &ret[0])
 
@@ -96,7 +124,9 @@ func TestCopyResultsBy4(t *testing.T) {
 			binary.BigEndian.PutUint32(expected[i*32+j*4:], m[i][j])
 		}
 	}
-	t.Errorf("got %x, expected %x\n", ret[:], expected[:])
+	if !bytes.Equal(ret[:], expected[:]) {
+		t.Errorf("got %x, expected %x\n", ret[:], expected[:])
+	}
 }
 
 func BenchmarkOneBlockBy4(b *testing.B) {