A bumper beam of a vehicle according to the present invention includes a pair of mounting portions for being fixed to a vehicle member, a supporting portion having a cross-section in which a front surface is closed and a rear surface opens and having both ends supporting the pair of mounting portions, a web disposed in front of the supporting portion, an energy absorbing portion supporting a rear surface of the web and supported by the front surface of the supporting portion to absorb energy generated when a colliding object collides to with the web, and an energy transmitting portion connecting the energy absorbing portion and the pair of mounting portions.