The invention discloses a pipeline welding process for a sloping field. Groove preparation is conducted on pipe openings of two pipelines, asymmetric double-V-shaped combined grooves are formed, and then locating, pairing, preheating, root welding, hot welding, filling welding, cosmetic welding are carried out in sequence, operation is easy, stability is high, labor cost is reduced, and meanwhile reliable weld quality can be guaranteed. Furthermore, the double-V-shaped combined grooves are adopted in the process, the size of the grooves is small, required filling welding material is less, and welding cost can be lowered as well.