diff --git a/tests/core/pyspec/eth2spec/test/deneb/sanity/test_blocks.py b/tests/core/pyspec/eth2spec/test/deneb/sanity/test_blocks.py
index 9a6c6a45b..50b975d3b 100644
--- a/tests/core/pyspec/eth2spec/test/deneb/sanity/test_blocks.py
+++ b/tests/core/pyspec/eth2spec/test/deneb/sanity/test_blocks.py
@@ -46,3 +46,20 @@ def test_one_blob(spec, state):
 @spec_state_test
 def test_max_blobs(spec, state):
     yield from run_block_with_blobs(spec, state, blob_count=spec.MAX_BLOBS_PER_BLOCK)
+
+
+@with_deneb_and_later
+@spec_state_test
+def test_incorrect_blob_tx_type(spec, state):
+    yield 'pre', state
+
+    block = build_empty_block_for_next_slot(spec, state)
+    opaque_tx, _, blob_kzg_commitments, _ = get_sample_opaque_tx(spec)
+    block.body.blob_kzg_commitments = blob_kzg_commitments
+    opaque_tx[0] == spec.uint8(0x04)  # incorrect tx type
+    block.body.execution_payload.transactions = [opaque_tx]
+    block.body.execution_payload.block_hash = compute_el_block_hash(spec, block.body.execution_payload)
+    signed_block = state_transition_and_sign_block(spec, state, block)
+
+    yield 'blocks', [signed_block]
+    yield 'post', state