My parents transferred money to my personal account from Asia through an local agent to US amount to buy a house. The amount of money is $500k. We used a local agent to transfer the money from a third country, because the local government does not want to transfer the money out of the country. Is there any problem with US bank, with IRS? We are not US citizen.

Amounts over 100K must be reported on form 3520 to the IRS at tax time, even though there will be no tax for a family gift. You will have other tax concerns and might want to see a tax consultant before you go too far into this (and you don't say whose name the house will be in). You will of course have a lawyer handle the purchase of a house and can get some help then regarding next year's filing, but a real estate lawyer may not know all the fine details of income taxes.