Hello,I'm indian an illegal immegrant (seman vissa).my girl friend is green card in US.we are planning to marry here in US.coz of that is possible to become legal here.

Yes, if your girlfriend and you are getting married and she will have her green card and legal status for at least 5 years after the marriage (that's how long you must wait) you should file a petition now with the department of immigration and naturalization. If she will not possess her green card that long, then no, you'll not be able to gain citizenship that way. You will still probably have to pass naturalization tests so be prepared.