To provide a light quantity adjusting device for adjusting exposure corresponding to high image quality and further maintaining compactness of the device, and to provide an image capturing apparatus mounted with the light quantity adjusting device.

The device includes: first/second ND filters reciprocating between a retreat position where they retreat from an exposure aperture of a bottom board A and an advance position where they advance thereto; first blade member C/second blade member E which support the first/second ND filters; first actuator G/second actuator H which drive and hold the first blade member C/second blade member E; an intermediate plate D forming moving space of the first ND filter between the first blade member C and the second blade member E; and a pressing member F.