Abstract: In order to research random vibration characteristics of longitudinal roadheader under random cutting load, a multi-rigid-body dynamics model of the longitudinal roadheader was established by use of ADAMS software. Vibration characteristics of cutting head, boom and body under axial drilling, vertical cutting and horizontal cutting were simulated. The simulation results show that axial drilling has the greatest influence on vibration of each part of the longitudinal roadheader, and vertical displacement response of random vibration is greater than horizontal displacement response of random vibration under axial drilling. There is little difference between horizontal displacement response and vertical displacement response of random vibration under vertical cutting and horizontal cutting. Horizontal cutting has the least influence on vibration of the body.