diff --git a/test/functional/getblocktemplate_proposals.py b/test/functional/getblocktemplate_proposals.py
index 777b20212c..311d9197ac 100755
--- a/test/functional/getblocktemplate_proposals.py
+++ b/test/functional/getblocktemplate_proposals.py
@@ -53,12 +53,17 @@ class GetBlockTemplateProposalTest(BitcoinTestFramework):
         self.log.info("getblocktemplate: Test valid block")
         assert_template(node, block, None)
 
+        self.log.info("submitblock: Test block decode failure")
+        assert_raises_jsonrpc(-22, "Block decode failed", node.submitblock, b2x(block.serialize()[:-15]))
+
         self.log.info("getblocktemplate: Test bad input hash for coinbase transaction")
         bad_block = copy.deepcopy(block)
         bad_block.vtx[0].vin[0].prevout.hash += 1
         bad_block.vtx[0].rehash()
         assert_template(node, bad_block, 'bad-cb-missing')
 
+        self.log.info("submitblock: Test invalid coinbase transaction")
+        assert_raises_jsonrpc(-22, "Block does not start with a coinbase", node.submitblock, b2x(bad_block.serialize()))
 
         self.log.info("getblocktemplate: Test truncated final transaction")
         assert_raises_jsonrpc(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(block.serialize()[:-1]), 'mode': 'proposal'})