A sensor device includes a substrate and a sensor chip held on the substrate. The substrate includes a flow channel. The sensor chip includes a plate. The plate includes a first surface and a second surface opposite to the first surface. A plurality of through holes each penetrates through the first surface and the second surface. A direction of a line segment connecting centers of any two adjacent through holes among the plurality of through holes is neither parallel nor perpendicular to the center line of the flow channel.
