A vehicle body front structure includes a pair of left and right front side frames which are installed at a front of a vehicle body, and extend in a fore-and-aft direction of the vehicle body; and a power unit disposed in a driving force transmission chamber between the left and right front side frames. The left and right front side frames include respective branch frames which extend from the left and right front side frames obliquely forward and outward in a vehicle width direction, rear ends of the branch frames penetrate through respective outer walls of the left and right front side frames, and extend along inner surfaces of the left and right front side frames, and a reinforcing member is integrally connected to each of intersection portions of the branch frames and the front side frames.