diff --git a/phasm/codestyle.py b/phasm/codestyle.py
index bbb7a05..fc40868 100644
--- a/phasm/codestyle.py
+++ b/phasm/codestyle.py
@@ -63,7 +63,7 @@ def expression(inp: ourlang.Expression) -> str:
         ) + ', )'
 
     if isinstance(inp, ourlang.ConstantStruct):
-        return inp.struct_name + '(' + ', '.join(
+        return inp.struct_type3.name + '(' + ', '.join(
             expression(x)
             for x in inp.value
         ) + ')'
diff --git a/phasm/ourlang.py b/phasm/ourlang.py
index f103555..df97b23 100644
--- a/phasm/ourlang.py
+++ b/phasm/ourlang.py
@@ -98,21 +98,21 @@ class ConstantStruct(ConstantMemoryStored):
     """
     A Struct constant value expression within a statement
     """
-    __slots__ = ('struct_name', 'value', )
+    __slots__ = ('struct_type3', 'value', )
 
-    struct_name: str
+    struct_type3: Type3
     value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']]
 
-    def __init__(self, struct_name: str, value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']], data_block: 'ModuleDataBlock') -> None:
+    def __init__(self, struct_type3: Type3, value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']], data_block: 'ModuleDataBlock') -> None:
         super().__init__(data_block)
-        self.struct_name = struct_name
+        self.struct_type3 = struct_type3
         self.value = value
 
     def __repr__(self) -> str:
         # Do not repr the whole ModuleDataBlock
         # As this has a reference back to this constant for its data
         # which it needs to compile the data into the program
-        return f'ConstantStruct({repr(self.struct_name)}, {repr(self.value)}, @{repr(self.data_block.address)})'
+        return f'ConstantStruct({self.struct_type3!r}, {self.value!r}, @{self.data_block.address!r})'
 
 class VariableReference(Expression):
     """
diff --git a/phasm/parser.py b/phasm/parser.py
index e32563a..9944dc2 100644
--- a/phasm/parser.py
+++ b/phasm/parser.py
@@ -584,7 +584,8 @@ class OurVisitor:
             if not isinstance(node.func.ctx, ast.Load):
                 _raise_static_error(node.func, 'Must be load context')
 
-            if node.func.id not in module.struct_definitions:
+            struct_def = module.struct_definitions.get(node.func.id)
+            if struct_def is None:
                 _raise_static_error(node.func, 'Undefined struct')
 
             if node.keywords:
@@ -600,7 +601,7 @@ class OurVisitor:
 
             data_block = ModuleDataBlock(struct_data)
             module.data.blocks.append(data_block)
-            return ConstantStruct(node.func.id, struct_data, data_block)
+            return ConstantStruct(struct_def.struct_type3, struct_data, data_block)
 
         _not_implemented(node.kind is None, 'Constant.kind')
 
diff --git a/phasm/type3/constraints.py b/phasm/type3/constraints.py
index c5bf372..4a9541b 100644
--- a/phasm/type3/constraints.py
+++ b/phasm/type3/constraints.py
@@ -392,10 +392,16 @@ class LiteralFitsConstraint(ConstraintBase):
         # gets updated when we figure out the type of the
         # expression the literal is used in
         res.extend(
-            SameTypeConstraint(x_t, PlaceholderForType([y]), comment=f'{self.literal.struct_name}.{x_n}')
+            SameTypeConstraint(x_t, PlaceholderForType([y]), comment=f'{self.literal.struct_type3.name}.{x_n}')
             for (x_n, x_t, ), y in zip(st_args, self.literal.value, strict=True)
         )
 
+        res.append(SameTypeConstraint(
+            self.literal.struct_type3,
+            self.type3,
+            comment='Struct types must match',
+        ))
+
         return res
 
     def _generate_tuple(self, tp_args: tuple[Type3, ...]) -> CheckResult:
diff --git a/tests/integration/test_lang/test_struct.py b/tests/integration/test_lang/test_struct.py
index 6b211e9..a0396ab 100644
--- a/tests/integration/test_lang/test_struct.py
+++ b/tests/integration/test_lang/test_struct.py
@@ -64,6 +64,36 @@ def helper(shape1: Rectangle, shape2: Rectangle) -> i32:
 
     assert 545 == result.returned_value
 
+@pytest.mark.integration_test
+def test_type_mismatch_struct_call_root():
+    code_py = """
+class CheckedValueBlue:
+    value: i32
+
+class CheckedValueRed:
+    value: i32
+
+CONST: CheckedValueBlue = CheckedValueRed(1)
+"""
+
+    with pytest.raises(Type3Exception, match='CheckedValueBlue must be CheckedValueRed instead'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_type_mismatch_struct_call_nested():
+    code_py = """
+class CheckedValueBlue:
+    value: i32
+
+class CheckedValueRed:
+    value: i32
+
+CONST: (CheckedValueBlue, u32, ) = (CheckedValueRed(1), 16, )
+"""
+
+    with pytest.raises(Type3Exception, match='CheckedValueBlue must be CheckedValueRed instead'):
+        Suite(code_py).run_code()
+
 @pytest.mark.integration_test
 @pytest.mark.parametrize('type_', ['i32', 'i64', 'f32', 'f64'])
 def test_type_mismatch_struct_member(type_):