In order to restrain the influence of non-stationary disturbance to VCM distillation process with integral characteristics by the acetylene method, an effective adaptive MPC method was presented. Due to the integral characteristics of the high boiling tower caused by settling of high-boiling residues to the bottom of tower, liquid level of the high boiling tower was taken as integral variable. Furthermore, in order to restrain the influence of non-stationary disturbance to liquid level of the high boiling tower caused by feed temperature of VCM and other factors, firstly, RELS (recursive extended least squares) algorithm was used to estimate the disturbance; secondly, the proportion of prediction error caused by the disturbance was calculated. Lastly, twiddle factor of adaptive MPC was updated real-time to realize the control of liquid level. Industrial experiments indicated that the adaptive MPC could overcome the non-stationary disturbance effectively, and standard deviation of liquid level was 2.6616 which was reduced by 60.7% than before. The effectiveness of the adaptive MPC was proved.