A pulse wave detecting device, comprising: a sensor section that includes an element row including a plurality of pressure detecting elements arranged in a first direction; an air bag that is configured to press the sensor section against a body surface of a living body in a state where the first direction crosses a direction of an artery extending below the body surface,; an air bag drive section that includes a pump, and configured to control an internal pressure of the air bag; a pressing force control section configured to control the air bag drive section for adjusting an amount of air held in the air bag, and thus control a pressing force applied by the sensor section; a rotation drive section configured to rotate the sensor section about an axis perpendicular to a pressing direction of the air bag and the first direction; a rotation control section configured to control the rotation drive section to rotate the sensor section; a rotation angle determining section configured to determine a rotation angle of the sensor section about the axis based on pressure signals detected by the pressure detecting elements in a state where the sensor section is pressed by the air bag against the body surface with a specific pressing force; and a storage control section configured to control, after determining the rotation angle, a pressing force applied to the sensor section by the air bag to a reset value smaller than the specific pressing force and larger than zero, increase the pressing force applied to the sensor section by the air bag from the reset value in a state where the sensor section is rotated about the axis based on the determined rotation angle, hold the pressing force at a pressing value determined based on pressure signals detected by the pressure detecting elements during increase of the pressing force from the reset value, and store, in a storage medium, pressure signals detected by a pressure detecting element selected from the plurality of pressure detecting elements based on the pressure signals detected by the pressure detecting elements during the increase. a sensor section that includes an element row including a plurality of pressure detecting elements arranged in a first direction; an air bag that is configured to press the sensor section against a body surface of a living body in a state where the first direction crosses a direction of an artery extending below the body surface,; an air bag drive section that includes a pump, and configured to control an internal pressure of the air bag; a pressing force control section configured to control the air bag drive section for adjusting an amount of air held in the air bag, and thus control a pressing force applied by the sensor section; a rotation drive section configured to rotate the sensor section about an axis perpendicular to a pressing direction of the air bag and the first direction; a rotation control section configured to control the rotation drive section to rotate the sensor section; a rotation angle determining section configured to determine a rotation angle of the sensor section about the axis based on pressure signals detected by the pressure detecting elements in a state where the sensor section is pressed by the air bag against the body surface with a specific pressing force; and a storage control section configured to control, after determining the rotation angle, a pressing force applied to the sensor section by the air bag to a reset value smaller than the specific pressing force and larger than zero, increase the pressing force applied to the sensor section by the air bag from the reset value in a state where the sensor section is rotated about the axis based on the determined rotation angle, hold the pressing force at a pressing value determined based on pressure signals detected by the pressure detecting elements during increase of the pressing force from the reset value, and store, in a storage medium, pressure signals detected by a pressure detecting element selected from the plurality of pressure detecting elements based on the pressure signals detected by the pressure detecting elements during the increase. control, after determining the rotation angle, a pressing force applied to the sensor section by the air bag to a reset value smaller than the specific pressing force and larger than zero, increase the pressing force applied to the sensor section by the air bag from the reset value in a state where the sensor section is rotated about the axis based on the determined rotation angle, hold the pressing force at a pressing value determined based on pressure signals detected by the pressure detecting elements during increase of the pressing force from the reset value, and store, in a storage medium, pressure signals detected by a pressure detecting element selected from the plurality of pressure detecting elements based on the pressure signals detected by the pressure detecting elements during the increase.