Bitcoin QT how to import wallet?

Paper wallet is piece of information includes your password to recover wallet. If you lose that password you lose the wallet. You can not generate then coins inside. It's very helpful you keep two copy of it. One is locked one is for backup some other place.from wiki i gather some info for you heop helps

Redeeming Keys and Withdrawing Funds

Paper wallets are very different from "live" wallets such as the Bitcoin-QT client in that it is not possible to transfer (withdraw) a portion of a paper wallet's bitcoin balance. The only way to withdraw funds from a paper wallet is to import or "sweep" the entire balance of the paper wallet to a new address, typically a live wallet or online exchange. Once the transfer has been confirmed, the paper wallet should no longer be used.
There are various methods for copying the private key data from a paper wallet to other wallets. bitcoind supports an "importprivkey" RPC method for this purpose. Bitcoin-Qt's debug console can also be used in a similar way (see also ). and can also import them directly into wallets. provides the ability to Add Funds using a private key: the exchange will then create a "sweep" transaction that spends any amount for that paper wallet address so that the amount is added to your account with them; it will also sweep to your account any bitcoins received to that address in the future as well.