There is no contract. If your bank requires one, then you're probably going to need to find another bank, or receive payment some other way. Which country is this?
Im From pakistan, have visited many bank but every one refused saying they need a contract.
Sounds like the bank you visited is mistaken. There are some forms you need to fill out but they're probably making you fill out forms that are not necessary. Could be the person you spoke with misunderstood you or the process. Check out this article about receiving wire transfers in Pakistan [abdussamad.com], which I found while researching this.
well i already have account in banks but they said, they can deposit cash and check only in local currency, for US dollars they need a proof/ source of income
Your best bet is probably to find someone in Pakistan who is receiving wire transfer payments and find out how they did it. I don't know if there are any here, but there might be some on the Google forum.
Or if you know of a site that is Pakistan based and running AdSense, you could try contacting them.
You can open a US account under the same account and receive wiretransfer from there. But there's a monthly fee.
If you don't earn that much with google then you're better off just receiving payment by checks.
Google also offers Western Union Quick Cash which may be your best bet. I found a few sites that mention this as a payment option for Pakistan but won't link to them. Google mentions this as an option on this page
How frustrating! What about showing them:
--Adsense terms and conditions, which stand in for a contract, plus
--A screenshot of your name and address in your Google account, and any other screens in your Google account which show that (a) you have a Google account and (b) you are being paid in that account and it's merely a matter of how you want to receive the money.
I have no idea if that will help. American banks are usually okay with seeing that you have received that income somehow, so maybe hold onto your next check and make a copy of it before depositing, so they can see your name, address, etc., on it.