Upheaval buckling of pipelines can occur under thermal expansion and differential ground settlement. Research on this phenomenon has usually assumed the pipes are buried in horizontal ground. For long-distance transmission pipelines across mountainous areas, the ground surface is commonly inclined. Based on the Rankine earth pressure theory and Mohr-Coulomb failure criterion, analytical formulae for calculating the peak uplift resistance and the slip surface angles for a buried pipe in inclined ground are presented in this paper. Analyses indicate that the slip surfaces in inclined ground are asymmetric and rotate towards the downhill side. Under a shallow burial depth, the failure plane angle is highly impacted by the ground inclination. When the embedment ratio (H/D) is more than 4, the influence of the ground slope on the failure plane angle is negligible. The peak uplift resistance reduces in inclined ground, especially when H/D is less than 1. Finally, a simple equation considering the impact of ground inclination is proposed to predict the peak uplift resistance.