diff --git a/sample/she_g1only.cpp b/sample/she_g1only.cpp
new file mode 100644
index 0000000..9dc5461
--- /dev/null
+++ b/sample/she_g1only.cpp
@@ -0,0 +1,71 @@
+#include <mcl/she.hpp>
+#include <mcl/elgamal.hpp>
+#include <cybozu/benchmark.hpp>
+
+using namespace mcl::she;
+
+const mcl::EcParam& g_para = mcl::ecparam::secp256k1;
+//const mcl::EcParam& g_para = mcl::ecparam::secp160k1;
+
+void elgamal()
+{
+	puts("elgamal");
+	struct TagZn;
+	typedef mcl::FpT<> Fp;
+	typedef mcl::FpT<TagZn> Zn;
+	typedef mcl::EcT<Fp> Ec;
+	typedef mcl::ElgamalT<Ec, Zn> ElgamalEc;
+	Ec P;
+	mcl::initCurve<Ec, Zn>(g_para.curveType, &P);
+	const size_t bitSize = Zn::getBitSize();
+	cybozu::RandomGenerator rg;
+
+	ElgamalEc::PrivateKey sec;
+	sec.init(P, bitSize, rg);
+	sec.setCache(0, 60000);
+	const ElgamalEc::PublicKey& pub = sec.getPublicKey();
+
+	const int m1 = 123;
+	const int m2 = 654;
+	ElgamalEc::CipherText c1, c2;
+	pub.enc(c1, m1);
+	pub.enc(c2, m2);
+	c1.add(c2);
+	Zn dec;
+	sec.dec(dec, c1);
+	std::cout << "dec=" << dec << std::endl;
+	CYBOZU_BENCH_C("enc", 1000, pub.enc, c1, m1);
+}
+
+int main()
+	try
+{
+	// initialize system
+	initG1only(g_para, 1024);
+
+	SecretKey sec;
+	sec.setByCSPRNG();
+	PublicKey pub;
+	sec.getPublicKey(pub);
+	PrecomputedPublicKey ppub;
+	ppub.init(pub);
+
+	int m1 = 123;
+	int m2 = 654;
+
+	CipherTextG1 c1, c2;
+	ppub.enc(c1, m1);
+	ppub.enc(c2, m2);
+	CYBOZU_BENCH_C("pub.enc", 1000, pub.enc, c1, m1);
+	CYBOZU_BENCH_C("ppub.enc", 1000, ppub.enc, c1, m1);
+	add(c1, c1, c2);
+	int m = sec.dec(c1);
+	printf("Dec(Enc(%d) + Enc(%d)) = %d(%s)\n", m1, m2, m, m == m1 + m2 ? "ok" : "ng");
+
+	elgamal();
+
+} catch (std::exception& e) {
+	printf("ERR %s\n", e.what());
+	return 1;
+}
+