diff --git a/include/mcl/she.h b/include/mcl/she.h
index 60b399c..d474216 100644
--- a/include/mcl/she.h
+++ b/include/mcl/she.h
@@ -163,6 +163,19 @@ MCLSHE_DLL_API int shePrecomputedPublicKeyEncG1(sheCipherTextG1 *c, const shePre
 MCLSHE_DLL_API int shePrecomputedPublicKeyEncG2(sheCipherTextG2 *c, const shePrecomputedPublicKey *ppub, mclInt m);
 MCLSHE_DLL_API int shePrecomputedPublicKeyEncGT(sheCipherTextGT *c, const shePrecomputedPublicKey *ppub, mclInt m);
 
+/*
+	enc large integer
+	buf[bufSize] is little endian
+	bufSize <= (FrBitSize + 63) & ~63
+	return 0 if success
+*/
+MCLSHE_DLL_API int sheEncIntVecG1(sheCipherTextG1 *c, const shePublicKey *pub, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int sheEncIntVecG2(sheCipherTextG2 *c, const shePublicKey *pub, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int sheEncIntVecGT(sheCipherTextGT *c, const shePublicKey *pub, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int shePrecomputedPublicKeyEncIntVecG1(sheCipherTextG1 *c, const shePrecomputedPublicKey *ppub, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int shePrecomputedPublicKeyEncIntVecG2(sheCipherTextG2 *c, const shePrecomputedPublicKey *ppub, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int shePrecomputedPublicKeyEncIntVecGT(sheCipherTextGT *c, const shePrecomputedPublicKey *ppub, const void *buf, mclSize bufSize);
+
 /*
 	m must be 0 or 1
 */
@@ -235,6 +248,15 @@ MCLSHE_DLL_API int sheSubGT(sheCipherTextGT *z, const sheCipherTextGT *x, const
 MCLSHE_DLL_API int sheMulG1(sheCipherTextG1 *z, const sheCipherTextG1 *x, mclInt y);
 MCLSHE_DLL_API int sheMulG2(sheCipherTextG2 *z, const sheCipherTextG2 *x, mclInt y);
 MCLSHE_DLL_API int sheMulGT(sheCipherTextGT *z, const sheCipherTextGT *x, mclInt y);
+/*
+	mul large integer
+	buf[bufSize] is little endian
+	bufSize <= (FrBitSize + 63) & ~63
+	return 0 if success
+*/
+MCLSHE_DLL_API int sheMulIntVecG1(sheCipherTextG1 *z, const sheCipherTextG1 *x, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int sheMulIntVecG2(sheCipherTextG2 *z, const sheCipherTextG2 *x, const void *buf, mclSize bufSize);
+MCLSHE_DLL_API int sheMulIntVecGT(sheCipherTextGT *z, const sheCipherTextGT *x, const void *buf, mclSize bufSize);
 
 // return 0 if success
 // z = x * y
diff --git a/include/mcl/she.hpp b/include/mcl/she.hpp
index 3ce3614..47e8796 100644
--- a/include/mcl/she.hpp
+++ b/include/mcl/she.hpp
@@ -1656,7 +1656,8 @@ public:
 		{
 			mul(z, x.c1_, y.c2_);
 		}
-		static void mul(CipherTextGT& z, const CipherTextGT& x, int64_t y)
+		template<class INT>
+		static void mul(CipherTextGT& z, const CipherTextGT& x, const INT& y)
 		{
 			for (int i = 0; i < 4; i++) {
 				GT::pow(z.g_[i], x.g_[i], y);
diff --git a/src/she_c_impl.hpp b/src/she_c_impl.hpp
index 073bc2b..8cfa6d0 100644
--- a/src/she_c_impl.hpp
+++ b/src/she_c_impl.hpp
@@ -274,6 +274,41 @@ int sheEncGT(sheCipherTextGT *c, const shePublicKey *pub, mclInt m)
 	return encT(c, pub, m);
 }
 
+bool setArray(mpz_class& m, const void *buf, mclSize bufSize)
+{
+	if (bufSize > Fr::getUnitSize() * sizeof(mcl::fp::Unit)) return false;
+	bool b;
+	mcl::gmp::setArray(&b, m, (const uint8_t*)buf, bufSize);
+	return b;
+}
+
+template<class CT>
+int encIntVecT(CT *c, const shePublicKey *pub, const void *buf, mclSize bufSize)
+	try
+{
+	mpz_class m;
+	if (!setArray(m, buf, bufSize)) return -1;
+	cast(pub)->enc(*cast(c), m);
+	return 0;
+} catch (std::exception&) {
+	return -1;
+}
+
+int sheEncIntVecG1(sheCipherTextG1 *c, const shePublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return encIntVecT(c, pub, buf, bufSize);
+}
+
+int sheEncIntVecG2(sheCipherTextG2 *c, const shePublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return encIntVecT(c, pub, buf, bufSize);
+}
+
+int sheEncIntVecGT(sheCipherTextGT *c, const shePublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return encIntVecT(c, pub, buf, bufSize);
+}
+
 template<class CT, class PK>
 int encWithZkpBinT(CT *c, sheZkpBin *zkp, const PK *pub, int m)
 	try
@@ -512,6 +547,33 @@ int sheMulGT(sheCipherTextGT *z, const sheCipherTextGT *x, mclInt y)
 	return mulT(*cast(z), *cast(x), y);
 }
 
+template<class CT>
+int mulIntVecT(CT& z, const CT& x, const void *buf, mclSize bufSize)
+	try
+{
+	mpz_class m;
+	if (!setArray(m, buf, bufSize)) return -1;
+	CT::mul(z, x, m);
+	return 0;
+} catch (std::exception&) {
+	return -1;
+}
+
+int sheMulIntVecG1(sheCipherTextG1 *z, const sheCipherTextG1 *x, const void *buf, mclSize bufSize)
+{
+	return mulIntVecT(*cast(z), *cast(x), buf, bufSize);
+}
+
+int sheMulIntVecG2(sheCipherTextG2 *z, const sheCipherTextG2 *x, const void *buf, mclSize bufSize)
+{
+	return mulIntVecT(*cast(z), *cast(x), buf, bufSize);
+}
+
+int sheMulIntVecGT(sheCipherTextGT *z, const sheCipherTextGT *x, const void *buf, mclSize bufSize)
+{
+	return mulIntVecT(*cast(z), *cast(x), buf, bufSize);
+}
+
 int sheMul(sheCipherTextGT *z, const sheCipherTextG1 *x, const sheCipherTextG2 *y)
 {
 	return mulT(*cast(z), *cast(x), *cast(y));
@@ -627,6 +689,33 @@ int shePrecomputedPublicKeyEncGT(sheCipherTextGT *c, const shePrecomputedPublicK
 	return pEncT(c, pub, m);
 }
 
+template<class CT>
+int pEncIntVecT(CT *c, const shePrecomputedPublicKey *pub, const void *buf, mclSize bufSize)
+	try
+{
+	mpz_class m;
+	if (!setArray(m, buf, bufSize)) return -1;
+	cast(pub)->enc(*cast(c), m);
+	return 0;
+} catch (std::exception&) {
+	return -1;
+}
+
+int shePrecomputedPublicKeyEncIntVecG1(sheCipherTextG1 *c, const shePrecomputedPublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return pEncIntVecT(c, pub, buf, bufSize);
+}
+
+int shePrecomputedPublicKeyEncIntVecG2(sheCipherTextG2 *c, const shePrecomputedPublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return pEncIntVecT(c, pub, buf, bufSize);
+}
+
+int shePrecomputedPublicKeyEncIntVecGT(sheCipherTextGT *c, const shePrecomputedPublicKey *pub, const void *buf, mclSize bufSize)
+{
+	return pEncIntVecT(c, pub, buf, bufSize);
+}
+
 template<class PK, class CT>
 int verifyT(const PK& pub, const CT& c, const ZkpBin& zkp)
 	try
diff --git a/test/she_c_test.hpp b/test/she_c_test.hpp
index 8287c0e..f5516d3 100644
--- a/test/she_c_test.hpp
+++ b/test/she_c_test.hpp
@@ -432,6 +432,40 @@ CYBOZU_TEST_AUTO(ZkpEq)
 	shePrecomputedPublicKeyDestroy(ppub);
 }
 
+template<class CT, class ENC, class ENCV, class DEC, class SUB, class MUL>
+void IntVecTest(const sheSecretKey& sec, const shePublicKey& pub, const ENC& enc, const ENCV& encv, const DEC& dec, const SUB& sub, const MUL& mul, uint8_t *buf, size_t bufSize)
+{
+	CT c1, c2;
+	int ret;
+	ret = encv(&c1, &pub, buf, bufSize);
+	CYBOZU_TEST_EQUAL(ret, 0);
+	buf[0] += 5;
+	enc(&c2, &pub, 1);
+	ret = mul(&c2, &c2, buf, bufSize);
+	CYBOZU_TEST_EQUAL(ret, 0);
+	sub(&c2, &c2, &c1);
+	int64_t d;
+	ret = dec(&d, &sec, &c2);
+	CYBOZU_TEST_EQUAL(ret, 0);
+	CYBOZU_TEST_EQUAL(d, 5);
+}
+
+CYBOZU_TEST_AUTO(IntVec)
+{
+	sheSecretKey sec;
+	sheSecretKeySetByCSPRNG(&sec);
+	shePublicKey pub;
+	sheGetPublicKey(&pub, &sec);
+	uint8_t buf[48];
+	size_t n = 32;
+	for (size_t i = 0; i < sizeof(buf); i++) {
+		buf[i] = uint8_t(i + 5);
+	}
+	IntVecTest<sheCipherTextG1>(sec, pub, sheEncG1, sheEncIntVecG1, sheDecG1, sheSubG1, sheMulIntVecG1, buf, n);
+	IntVecTest<sheCipherTextG2>(sec, pub, sheEncG2, sheEncIntVecG2, sheDecG2, sheSubG2, sheMulIntVecG2, buf, n);
+	IntVecTest<sheCipherTextGT>(sec, pub, sheEncGT, sheEncIntVecGT, sheDecGT, sheSubGT, sheMulIntVecGT, buf, n);
+}
+
 CYBOZU_TEST_AUTO(finalExp)
 {
 	sheSecretKey sec;