In this study, the effects of partial slip on the peristaltic flow of a MHD Newtonian fluid in an asymmetric channel are studied analytically and numerically. The governing equations of motion and energy are simplified using a long wavelength approximation. A closed form solution of the momentum equation is obtained by the homotopy perturbation method (HPM) and an exact solution of the energy equation is presented in the presence of the viscous dissipation term. The expression for pressure rise is calculated using numerical integration. Also, we discussed the trapping phenomena. The graphical results are presented to interpret various physical parameter of interest. (C) 2010 Elsevier Ltd. All rights reserved.