diff --git a/gen/gen_code.cpp b/gen/gen_code.cpp
index 41c24c8..60325a6 100644
--- a/gen/gen_code.cpp
+++ b/gen/gen_code.cpp
@@ -640,6 +640,23 @@
 			uint8 ext;
 			const char *name;
 		} tbl[] = {
+			{ 0xa3, 4, "bt" },
+			{ 0xab, 5, "bts" },
+			{ 0xb3, 6, "btr" },
+			{ 0xbb, 7, "btc" },
+		};
+		for (int i = 0; i < NUM_OF_ARRAY(tbl); i++) {
+			const Tbl *p = &tbl[i];
+			printf("void %s(const Operand& op, const Reg& reg) { opModRM(reg, op, op.isREG(16|32|64) && op.getBit() == reg.getBit(), op.isMEM(), 0x0f, 0x%02x); }\n", p->name, p->code);
+			printf("void %s(const Operand& op, uint8 imm) { opR_ModM(op, 16|32|64, %d, 0x0f, 0xba); db(imm); }\n", p->name, p->ext);
+		}
+	}
+	{
+		const struct Tbl {
+			uint8 code;
+			uint8 ext;
+			const char *name;
+		} tbl[] = {
 			{ B11110110, 6, "div" },
 			{ B11110110, 7, "idiv" },
 			{ B11110110, 5, "imul" },
diff --git a/readme.md b/readme.md
index 78617c5..d363a8c 100644
--- a/readme.md
+++ b/readme.md
@@ -1,5 +1,5 @@
 
-Xbyak 4.60 ; JIT assembler for x86(IA32), x64(AMD64, x86-64) by C++
+Xbyak 4.61 ; JIT assembler for x86(IA32), x64(AMD64, x86-64) by C++
 =============
 
 Abstract
@@ -269,6 +269,7 @@
 
 History
 -------------
+* 2014/May/30 ver 4.61 support bt, bts, btr, btc
 * 2014/May/28 ver 4.60 support vcvtph2ps, vcvtps2ph
 * 2014/Apr/11 ver 4.52 add detection of rdrand
 * 2014/Mar/25 ver 4.51 remove state information of unreferenced labels
diff --git a/readme.txt b/readme.txt
index 07851c9..d2f9318 100644
--- a/readme.txt
+++ b/readme.txt
@@ -1,5 +1,5 @@
 
-    C++用x86(IA-32), x64(AMD64, x86-64) JITアセンブラ Xbyak 4.60
+    C++用x86(IA-32), x64(AMD64, x86-64) JITアセンブラ Xbyak 4.61
 
 -----------------------------------------------------------------------------
 ◎概要
@@ -285,6 +285,7 @@
 -----------------------------------------------------------------------------
 ◎履歴
 
+2014/05/30 ver 4.61 bt, bts, btr, btcのサポート
 2014/05/28 ver 4.60 vcvtph2ps, vcvtps2phのサポート
 2014/04/11 ver 4.52 rdrandの判定追加
 2014/03/25 ver 4.51 参照されなくなったラベルの状態を削除する
diff --git a/test/make_nm.cpp b/test/make_nm.cpp
index 2152f29..5b968dd 100644
--- a/test/make_nm.cpp
+++ b/test/make_nm.cpp
@@ -829,6 +829,22 @@
 			put(p, REG8|REG8_3|AL, IMM|NEG8);
 		}
 	}
+	void putBt() const
+	{
+		static const char tbl[][16] = {
+			"bt",
+			"bts",
+			"btr",
+			"btc",
+		};
+		for (size_t i = 0; i < NUM_OF_ARRAY(tbl); i++) {
+			const char *p = tbl[i];
+			put(p, MEM|REG16, REG16);
+			put(p, MEM|REG32, REG32);
+			put(p, MEM|REG64, REG64);
+			put(p, MEM16|REG16, IMM);
+		}
+	}
 	void putRorM() const
 	{
 		static const char tbl[][16] = {
@@ -2121,6 +2137,7 @@
 #else
 		putSIMPLE();
 		putReg1();
+		putBt();
 		putRorM();
 		separateFunc();
 		putPushPop();
diff --git a/xbyak/xbyak.h b/xbyak/xbyak.h
index 1947a27..3635bf6 100644
--- a/xbyak/xbyak.h
+++ b/xbyak/xbyak.h
@@ -91,7 +91,7 @@
 
 enum {
 	DEFAULT_MAX_CODE_SIZE = 4096,
-	VERSION = 0x4600 /* 0xABCD = A.BC(D) */
+	VERSION = 0x4610 /* 0xABCD = A.BC(D) */
 };
 
 #ifndef MIE_INTEGER_TYPE_DEFINED
diff --git a/xbyak/xbyak_mnemonic.h b/xbyak/xbyak_mnemonic.h
index f8ba5a5..8748102 100644
--- a/xbyak/xbyak_mnemonic.h
+++ b/xbyak/xbyak_mnemonic.h
@@ -1,4 +1,4 @@
-const char *getVersionString() const { return "4.60"; }
+const char *getVersionString() const { return "4.61"; }
 void packssdw(const Mmx& mmx, const Operand& op) { opMMX(mmx, op, 0x6B); }
 void packsswb(const Mmx& mmx, const Operand& op) { opMMX(mmx, op, 0x63); }
 void packuswb(const Mmx& mmx, const Operand& op) { opMMX(mmx, op, 0x67); }
@@ -441,6 +441,14 @@
 #endif
 void dec(const Operand& op) { opIncDec(op, 0x48, 1); }
 void inc(const Operand& op) { opIncDec(op, 0x40, 0); }
+void bt(const Operand& op, const Reg& reg) { opModRM(reg, op, op.isREG(16|32|64) && op.getBit() == reg.getBit(), op.isMEM(), 0x0f, 0xa3); }
+void bt(const Operand& op, uint8 imm) { opR_ModM(op, 16|32|64, 4, 0x0f, 0xba); db(imm); }
+void bts(const Operand& op, const Reg& reg) { opModRM(reg, op, op.isREG(16|32|64) && op.getBit() == reg.getBit(), op.isMEM(), 0x0f, 0xab); }
+void bts(const Operand& op, uint8 imm) { opR_ModM(op, 16|32|64, 5, 0x0f, 0xba); db(imm); }
+void btr(const Operand& op, const Reg& reg) { opModRM(reg, op, op.isREG(16|32|64) && op.getBit() == reg.getBit(), op.isMEM(), 0x0f, 0xb3); }
+void btr(const Operand& op, uint8 imm) { opR_ModM(op, 16|32|64, 6, 0x0f, 0xba); db(imm); }
+void btc(const Operand& op, const Reg& reg) { opModRM(reg, op, op.isREG(16|32|64) && op.getBit() == reg.getBit(), op.isMEM(), 0x0f, 0xbb); }
+void btc(const Operand& op, uint8 imm) { opR_ModM(op, 16|32|64, 7, 0x0f, 0xba); db(imm); }
 void div(const Operand& op) { opR_ModM(op, 0, 6, 0xF6); }
 void idiv(const Operand& op) { opR_ModM(op, 0, 7, 0xF6); }
 void imul(const Operand& op) { opR_ModM(op, 0, 5, 0xF6); }