diff --git a/src/arch/i386.ins b/src/arch/i386.ins
index 5723736..37ad5d2 100644
--- a/src/arch/i386.ins
+++ b/src/arch/i386.ins
@@ -238,5 +238,15 @@
 { "btr",	0x0fba,		OP2F, OP_RMW_D8+6,OP_S8,     AOT_NONE	},
 { "btr",	0x0fba,		OP2F, OP_RMW_DW+6,OP_S8,     AOT_NONE	},
 { "btr",	0x0fba,		OP2F, OP_RMW_RW+6,OP_S8,     AOT_NONE	},
+/* BTS		0x0fab		2     r/mW        rW			*/
+{ "bts",	0x0fab,		OP2F, OP_RMW_D0_R,OP_RW,     AOT_NONE	},
+{ "bts",	0x0fab,		OP2F, OP_RMW_D8_R,OP_RW,     AOT_NONE	},
+{ "bts",	0x0fab,		OP2F, OP_RMW_DW_R,OP_RW,     AOT_NONE	},
+{ "bts",	0x0fab,		OP2F, OP_RMW_RW_R,OP_RW,     AOT_NONE	},
+/* BTS		0x0fba /5 ib	2     r/mW        imm8			*/
+{ "bts",	0x0fba,		OP2F, OP_RMW_D0+5,OP_S8,     AOT_NONE	},
+{ "bts",	0x0fba,		OP2F, OP_RMW_D8+5,OP_S8,     AOT_NONE	},
+{ "bts",	0x0fba,		OP2F, OP_RMW_DW+5,OP_S8,     AOT_NONE	},
+{ "bts",	0x0fba,		OP2F, OP_RMW_RW+5,OP_S8,     AOT_NONE	},
 /* NOP									*/
 { "nop",	0x90,		OP1F, AOT_NONE,   AOT_NONE,  AOT_NONE	},
diff --git a/test/i386.S b/test/i386.S
index c131de9..0bf5f5f 100644
--- a/test/i386.S
+++ b/test/i386.S
@@ -69,5 +69,10 @@
 	btr	[%eax], %ecx			/* 0f b3 08		*/
 	btr	%eax, $0x42			/* 0f ba f0 42		*/
 	btr	[%eax], $0x42			/* 0f ba 30 42		*/
+	/* BTS */
+	bts	%eax, %ecx			/* 0f ab c8		*/
+	bts	[%eax], %ecx			/* 0f ab 08		*/
+	bts	%eax, $0x42			/* 0f ba e8 42		*/
+	bts	[%eax], $0x42			/* 0f ba 28 42		*/
 	/* NOP */
 	nop