A shift control method for a dual clutch transmission (DCT) vehicle may include, performed by a controller of the DCT, an actual shift determining step, a cooperation control termination determining step, a flare determining step, an engine torque reducing step, a torque adding step, an engine torque raising step, and a shift finishing step of reducing an amount of reduction of the engine torque until synchronization is completed in proportion to a synchronization prediction time in which it takes an engine speed to reach a synchronization speed when the synchronization prediction time is smaller than a reference time during which the torque adding step and the engine torque raising step are performed, and having slip control over an engagement-side clutch.