A method for preventing engine stall of a vehicle includes detecting, by a control portion, whether a purge control valve becomes short to ground or not, determining, by the control portion, how rich a fuel is that has flowed into the engine using an oxygen sensor when it is determined that the purge control valve becomes short to ground in the detecting step, and controlling, by the control portion, a target RPM of the engine to be increased when it is determined that the fuel is rich in the determining step.