According to one embodiment, a strain detection device includes a first sensor sheet and a second sensor sheet opposed to the first sensor sheet with a base sandwiched therebetween, and a controller which drives the first sensor sheet and the second sensor sheet. Each of the first sensor sheet and the second sensor sheet includes strain gauges arranged in a row, power supply lines and first signal lines connected to first ends of the strain gauges, and ground lines and second signal lines connected to second ends of the strain gauges. Each of the ground lines of the first sensor sheet is connected to corresponding one of the power supply lines of the second sensor sheet.