Abstract: In order to study the influence of coal stress on drilling parameters of drilling rig, a simulation experiment equipment for measurement while drilling was developed, which can simulate four influencing factors of drilling pressure, confining pressure, coal strength and bit size. The equipment was mainly composed of drilling system, loading system and data measurement system, which can monitor drilling parameters such as torque, rotational speed and drilling displacement in real time. The drilling experiments of measurement while drilling of coal-like specimens under different drilling pressures and confining pressures were carried out with the equipment. The results show that during the drilling process, the curve of drilling depth-time is basically linear. The drilling rate is close to a constant, and the rotating speed increases rapidly at first and then remains stable. The torque fluctuates up and down after rapid growth. The torque and drilling speed increases with the increase of drilling pressure, approximately linear, and the speed decreases with the increase of drilling pressure, which is negatively correlated. Under the same drilling pressure, the torque increases with the increase of confining pressure. Under the same confining pressure, the torque increases with the increase of drilling pressure. The drilling speed and rotating speed decrease with the increase of confining pressure, which is negatively correlated.