Can i play basketball if i have deep vein thombrosis ?

Depends: Do you have acute DVT? if yes, you need to be on blood thinners and contact sport would not be advisable. If you had DVT and are not on blood thinners, you may play.

DVT: Usually you should wait 2 weeks after a dvt to exercise in order to give the clot a chance to attach firmly. I don't consider basketball to be a contact sport, however there is chance of injury which would make being on anticoagulant therapy dangerous should you fall and hit your head,for example.