I deploy too many contracts, so how to delete all contract records in mist wallet using one operation?
If the contracts have already been mined, you cannot remove them from the ledger.
However, if your code had a kill switch, you can call it on all but 1.
In your Ethereum Walltet click on contracts and then click on the contract you want to delete. When the contract is displayed move your mouse pointer on the contract name. Then you will see a trash symbol next to the contract name. Click on this symbol.A popup window will appear where you have to enter "delete" and press OK.