Pradeep,
1) NOC (No objection certificate) from your company with salary >5000
2) marriage certificate copy
3) Your ID copy (RP) - sponsor
4) passport copy of your wife

Fill up a form there.
+
bank card (200 QAR)

Optional (better take it with you)
degree certificate copy,job contract, passport copy
They will issue 1 month visa, after you can renew 5 more months. For renewal you have to take your wife for medical within a week after arrival.

Ahmed,
Yes, for visit visa. Salary > 5000 QAR must