Abstract: A package-type flow sensor includes a flow sensor chip having a sensor part configured to detect a flow of fluid, a package including a flat board part, forming an accommodating chamber configured to accommodate the flow sensor chip, and a connection terminal, provided on an outer surface of the board part, and connected to an external board. Further, in this package-type flow sensor, the board part is provided with a first vent hole communicating to inside and outside of the accommodating chamber, the package is provided with a second vent hole communicating to the inside and the outside of the accommodating chamber, at a position different from the board part, and the flow sensor chip is disposed on a flow passage of the fluid formed by the first vent hole and the second vent hole.