Following documents are required:-
1. 6 Months Bank statement with bank seal.
2. NOC letter from company in Arabic.
3. Company CR Copy
4. Electric Bill
5. Visa Application in Arabic
6. Your Degree certificate attested from MEA Qatar.
7. Your Marriage certificate attested from MEA Qatar.
8. if You are having Children birth certificate attested from MEA Qatar.
9. Passport copy of your wife.
10. Passport Copy of your Kid.
11. Nowdays they are asking rental contract also.

Except NOC Letter and application all documents Photo copies are only to be submitted.

Arrange all above documents and go to Labour Office location near Muntaza, they will give you a receipt.Check the visa status on internet
In addition to the previous reply you also need these documents
1. Your passport copy with you Visa stamp.
2. Your Qatar ID Copy.

Thanks