A flow path switching device includes: a first passage portion; a second passage portion; a first cover member attached to the first passage portion; and a second cover member attached to the second passage portion. The first passage portion includes a first passage connected to a fluid circuit and having a groove shape. The second passage portion includes a second passage connected to the fluid circuit to communicate with the first passage at a plurality of places and having a groove shape. The first passage portion, the second passage portion, and a drive unit are stacked in this order. The first cover member includes: a sealing portion to seal an opened portion of the first passage; and an opening arranged along an outer edge of the opened portion of the first passage.