A vehicle body on which a high voltage battery is mounted is provided. The vehicle body includes a vehicle body floor on which a battery is placed stably, side sills disposed on both lateral sides of the vehicle body floor, respectively, to extend in forward and backward directions, a plurality of coupling members, wherein front portions of the coupling members are combined with respective front side members, rear portions of the coupling members are combined with the side sills, respectively, and each coupling member connects, in an extension line, between the respective front side member and the respective side sill in the forward and backward directions, and a cross member that extends across the vehicle body floor and couples the coupling members, wherein each end of the cross member is combined with the respective side sill.