An oil pan structure (1) includes a lower structure (2) fixed to a lower portion of an engine block, a main oil pan (3) provided under an engine block with the lower structure being between the main oil pan and the engine block, a sub oil pan (5) that is provided in the main oil pan (3) and forms a first chamber (6) and a second chamber (7) inside the main oil pan (3). The sub oil pan (5) is separated into an upper body (5a) and a lower body (5b). The upper body (5a) is formed together with the lower structure (2) by injection molding.