The present invention provides a pulse wave detector capable of accurately detecting a pressure pulse wave in the state in which a flexible sensor is pressed against a body surface, a biological information measurement device, a method for controlling the pulse wave detector, and a program for controlling the pulse wave detector. The pulse wave detector is equipped with a flexible strain sensor 4 having a plurality of strain detection elements 41 arranged on a substrate 40 an air bag 3 to which the strain sensor 4 is fixed and a control section 12 for determining the timing at which the deformation of the detection face 42 of the strain sensor 4 has been stopped based on the strain detection signal detected by each of the strain detection elements in a pressure raising process in which the internal pressure of the air bag 3 is increased and for setting the level of the strain detection signal detected by each of the strain detection elements at the timing to a reference level. The control section 12 calibrates the strain detection signal detected by each of the strain detection elements 41 after the above-mentioned timing based on the above-mentioned reference level, converts the calibrated strain detection signal into a pressure signal, and stores the pressure signal in a memory 15.
