The invention discloses a bidirectional static and dynamic loading roof key block caving test device and method, and the device comprises an overall frame, a lateral pressure loading system, a vertical pressure loading system, a lateral pendulum bob impact disturbance system, a vertical drop-hammer impact disturbance system, an incident wave monitoring system and a response measurement system. Thetesting method comprises the steps: a first work condition: carrying out the bidirectional static and dynamic loading disturbance testing of a tunnel overall model sample to explore the initial stress state of the surrounding rocks of a tunnel and the initial stress condition of a key block rock, and observing an overall phenomena of the propagation law of cracks, a forming process of a key blockand the instability of the key block in the disturbance process; a second work condition: carrying out the bidirectional static and dynamic loading disturbance instability testing of a key block model sample, taking the result under the first work condition as the basis, abstracting the key block and the surrounding rocks at two sides to more precisely explore the law that a stress wave causes the propagation of cracks, a critical condition that the key block slides in an instable manner, and an action mechanism that the disturbance effect causes the instability.