The sliding surfaces of rock slopes are difficult to determined, which made a big obstacle to analyze the stability of rock slopes. This paper provides analytical solutions for rock slopes with single plane shear sliding failure mode, which represented by the plane with most potential sliding inclination angle. Noticing that tension cracks play an important role in stability of rock slopes. The analytical solutions including the potential sliding surfaces for two or multi steps rock slopes with incline or vertical cracks. An practical landslide was used to validate the accuracy of the proposed approach and several illustrate examples are taken to investigate the stability of rock slopes with various steps and incline/vertical cracks. As shown by the illustrate examples presented herein, the proposed solutions can provide an accurate and efficient way to determine the potential sliding surface of rock slopes. The rock slopes with incline cracks are more stable than those with vertical cracks. The factor of safety of slopes decrease with the increasing depth of the cracks. The incline angle of cracks have great influence on the stability of slopes. Traditionally, ignoring the influence of inclination of tension cracks may lead to unconservative estimations of slope stability.