VEHICLE BODY LATERAL SECTION STRUCTURE

A vehicle body lateral section structure () is provided with a center pillar inner (), a center pillar stiffener (), a partitioning member (), a filling material, a center pillar outer (), and a sound insulation member (). The center pillar stiffener forms a first closed cross-sectional portion () together with the center pillar inner. The partitioning member partitions a filling space () communicating with a first filling port and a second filling port inside the first closed cross-sectional portion. The center pillar outer forms a second closed cross-sectional portion () together with the center pillar stiffener. The sound insulation member is provided inside the second closed cross-sectional portion and foams when heated.