diff --git a/src/arm/Negate.go b/src/arm/Negate.go
new file mode 100644
index 0000000..2e7a33c
--- /dev/null
+++ b/src/arm/Negate.go
@@ -0,0 +1,8 @@
+package arm
+
+import "git.urbach.dev/cli/q/src/cpu"
+
+// NegateRegister negates the value in the source register and writes it to the destination register.
+func NegateRegister(destination cpu.Register, source cpu.Register) uint32 {
+	return 0b11001011<<24 | reg3Imm(destination, ZR, source, 0)
+}
diff --git a/src/arm/Negate_test.go b/src/arm/Negate_test.go
new file mode 100644
index 0000000..65f3809
--- /dev/null
+++ b/src/arm/Negate_test.go
@@ -0,0 +1,26 @@
+package arm_test
+
+import (
+	"testing"
+
+	"git.urbach.dev/cli/q/src/arm"
+	"git.urbach.dev/cli/q/src/cpu"
+	"git.urbach.dev/go/assert"
+)
+
+func TestNegateRegister(t *testing.T) {
+	usagePatterns := []struct {
+		Destination cpu.Register
+		Source      cpu.Register
+		Code        uint32
+	}{
+		{arm.X0, arm.X0, 0xCB0003E0},
+		{arm.X1, arm.X1, 0xCB0103E1},
+	}
+
+	for _, pattern := range usagePatterns {
+		t.Logf("neg %s, %s", pattern.Destination, pattern.Source)
+		code := arm.NegateRegister(pattern.Destination, pattern.Source)
+		assert.DeepEqual(t, code, pattern.Code)
+	}
+}
diff --git a/src/asmc/ARM.go b/src/asmc/ARM.go
index c6439b3..1d98cb1 100644
--- a/src/asmc/ARM.go
+++ b/src/asmc/ARM.go
@@ -307,6 +307,13 @@ func (c *compiler) ARM(x asm.Instruction) {
 			panic("not implemented")
 		}
 
+	case asm.NEGATE:
+		switch x.Type {
+		case asm.TypeRegister:
+			operands := c.assembler.Param.Register[x.Index]
+			c.append(arm.NegateRegister(operands.Register, operands.Register))
+		}
+
 	default:
 		panic("unknown mnemonic: " + x.Mnemonic.String())
 	}