A side structure for a vehicle body, the side structure having: a side rail and a pillar that are provided at sides of door openings; and trim members that are provided to the side rail and the pillar. In the side structure, a pillar inner member is provided to the side rail while the upper end of the pillar inner member overlaps a joint of the side rail, and this forms intersections at which rail flanges and pillar flanges cross. At the intersections, stepped sections are formed at the pillar flanges, and in the rail flanges, recesses are formed at portions corresponding to the stepped sections.