SYSTEM AND METHOD OF SECURING BRAKE BOOSTER NEGATIVE PRESSURE

A method of securing brake booster negative pressure is provided. The method includes operating a purge pump that is connected to a canister having evaporation gas absorbed thereon and a brake booster and determining whether the evaporation gas is injected into an intake pipe by the operation of the purge pump. Whether a negative pressure of the brake booster is insufficient is determined and when the evaporation gas is being injected into the intake pipe and the negative pressure is insufficient, a degree of opening of a valve provided in a line connecting the canister and the purge pump is adjusted.