To provide a circuit board testing device capable of bringing a probe into contact with a measuring point on a circuit board with a proper pressure, concerning the circuit board testing device having a circuit board holding tool for holding the circuit board and a probe holding tool for holding the probe for measuring the measuring point in contact with the measuring point on the circuit board.

The probe holding tool is provided with a probe pressing mechanism comprising a linear guide 57; a screw stock 59 arranged along the guide 57, and supported rotatably around the center axis and movably in the center axis direction; a slider 63 engaged movably with the guide 57, provided with the probe 73, and having a female screw hole 63a formed thereon to be screwed with the screw stock 59; a bent part (stopper) 55a on which the screw stock 59 abuts, for forbidding movement in one direction among movements in the center axis direction of the screw stock 59; and a spring (elastic member) 65 abutting on the bent part 55a and the slider 63, for pressing the slider 63 in the direction wherein the screw stock 59 abuts on the bent part 55a.