diff --git a/src/compiler.cairo b/src/compiler.cairo
index 6444ac72..5f9991ce 100644
--- a/src/compiler.cairo
+++ b/src/compiler.cairo
@@ -40,6 +40,7 @@ pub impl CompilerTraitImpl of CompilerTrait {
         opcodes.insert('OP_1ADD', Opcode::OP_1ADD);
         opcodes.insert('OP_ADD', Opcode::OP_ADD);
         opcodes.insert('OP_MAX', Opcode::OP_MAX);
+        opcodes.insert('OP_WITHIN', Opcode::OP_WITHIN);
         Compiler { opcodes }
     }
 
diff --git a/src/opcodes/opcodes.cairo b/src/opcodes/opcodes.cairo
index 6354b3e1..b430ba5b 100644
--- a/src/opcodes/opcodes.cairo
+++ b/src/opcodes/opcodes.cairo
@@ -21,6 +21,7 @@ pub mod Opcode {
     pub const OP_1ADD: u8 = 139;
     pub const OP_ADD: u8 = 147;
     pub const OP_MAX: u8 = 164;
+    pub const OP_WITHIN: u8 = 165;
 
     use shinigami::engine::Engine;
     use shinigami::stack::ScriptStackTrait;
@@ -191,6 +192,7 @@ pub mod Opcode {
             162 => not_implemented(ref engine),
             163 => not_implemented(ref engine),
             164 => opcode_max(ref engine),
+            165 => opcode_within(ref engine),
             _ => not_implemented(ref engine)
         }
     }
@@ -234,4 +236,15 @@ pub mod Opcode {
             b
         });
     }
+
+    fn opcode_within(ref engine: Engine) {
+        let max = engine.dstack.pop_int();
+        let min = engine.dstack.pop_int();
+        let value = engine.dstack.pop_int();
+        engine.dstack.push_int(if value >= min && value < max {
+            1
+        } else {
+            0
+        });
+    }
 }
diff --git a/src/opcodes/tests/test_opcodes.cairo b/src/opcodes/tests/test_opcodes.cairo
index 29f593f6..bd683a52 100644
--- a/src/opcodes/tests/test_opcodes.cairo
+++ b/src/opcodes/tests/test_opcodes.cairo
@@ -70,6 +70,25 @@ fn test_op_max() {
     assert_eq!(dstack, expected_stack.span(), "Stack is not equal to expected");
 }
 
+#[test]
+fn test_op_within() {
+    let program = "OP_1 OP_0 OP_1 OP_WITHIN";
+    let mut compiler = CompilerTraitImpl::new();
+    let bytecode = compiler.compile(program);
+    let mut engine = EngineTraitImpl::new(bytecode);
+    let _ = engine.step();
+    let _ = engine.step();
+    let _ = engine.step();
+    let res = engine.step();
+    assert!(res, "Execution of run failed");
+
+    let dstack = engine.get_dstack();
+    assert_eq!(dstack.len(), 1, "Stack length is not 1");
+
+    let expected_stack = array!["\0\0\0\0\0\0\0\0"];
+    assert_eq!(dstack, expected_stack.span(), "Stack is not equal to expected");
+}
+
 fn test_op_depth_empty_stack() {
     let program = "OP_DEPTH";
     let mut compiler = CompilerTraitImpl::new();