A vehicle body front section structure is provided including a battery pack, a lower cross member, and an impact absorbing structure. The battery pack is mounted at a vehicle lower side of a floor panel of a vehicle. The lower cross member is disposed at the vehicle lower side of a front cross member at a lower section of a front end of the vehicle, and extends along a vehicle width direction. The impact absorbing structure is provided between the lower cross member and the battery pack, and absorbs collision energy from collision load input from a vehicle front side.