A brake lamp control method of a vehicle is provided. The method includes determining whether a deceleration of the vehicle based on regenerative brake through the electric motor is present in a hysteresis period between an off threshold as a reference for turning off a brake lamp and an on threshold as a reference for turning on the brake lamp. When the deceleration of the vehicle is present in the hysteresis period, the method includes determining a state of the brake lamp before the deceleration of the vehicle enters the hysteresis period. In response to determining that the brake lamp is turned on or off for a reason except for the regenerative brake before the deceleration of the vehicle enters the hysteresis period, a request for turning on the brake lamp is set or reset based on the regenerative brake in response to the determined state of the brake lamp.