According to the invention, there is provided a connecting rod bearing constituted by a half bearing, which has a main cylindrical portion, crush reliefs and a transitional region. The crush relief is formed so that a depth from a virtual inner circumferential surface at a position of an end surface of the half bearing in a circumferential direction is larger than a depth from the virtual inner circumferential surface at a position where the crush relief connects with the transitional region. Further, a plurality of circumferential grooves are provided in the main cylindrical portion to continuously extend in the circumferential direction throughout an entire length of the main cylindrical portion in the circumferential direction, and are continuously provided also in the transitional region.