I have deployed contract using mist browser 0.6.1
How can I do code validity check on ethereum mist?
Your answer is in the web3.js documentation.
web3.eth.contract()with the ABI to create a web3.js contract instance.
.new()function on your contract instance with contract constructor parameters
web3.eth.getCode(). Compare the code to what you sent.
This outline of course is for web3.js, but in general you could do the same or similar steps in the geth console, from python, or one of the blockchain browsers.