A drink cup having an automatic retractable straw is disclosed herein. It comprises a main body having an outer cup, an inner cup having a guide inclined surface at a bottom thereof, and a vacuum insulation layer between the outer cup and the inner cup; a lid covered on the main body and having an opening at one side thereof for corresponding to an upper end of the guide inclined surface, a containing groove adjacent to the opening on a top surface thereof, and a flip cover pivotally disposed on the containing groove and having a convex part corresponding to the opening; and a straw accommodated in the inner cup and having a connecting member formed with a first perforation at one end thereof for connecting to an upper end of the straw and a second perforation corresponding to the bonding part of the lid at the other end thereof.