Using the conventional data, sounding data, NCEP/NCAR 1 ° × 1 ° reanalysis data and new generation weather radar data of regional automatic weather stations, the paper analyzes the occurrence and development mechanism of a hail weather process in the western Tarim Basin on July 2, 2018. The results show that: (1) The main influence system of the hail weather was caused by the continuous splitting of short waves in the southern section of the lower Siberian trough crossing the Pamirs; the hail weather occurrence time section was mainly in the area where warm and low pressure and cold air meet, and the ground convergence was the trigger mechanism for this hail weather. (2) The easterly winds appearing in the eastern to central regions of the southern Xinjiang Basin played an air cushion role, and the emergence of ground heat and low pressure enhanced the convergence of the ground near the ground. (3) There was obvious wind speed convergence in the ground layer of the area from Kashi Prefecture to Tumxuk in Xinjiang prior to the genration of the convective cell storm, which was favorable to the occurrence of local hail weather. (4) The radar reflectivity factor strong center corresponds to the large value region of the reflectivity factor gradient, which has a good indication for the identification and early warning of the hail cloud, and the intensity of the echo top was presented as banded distribution and small range, large intensity gradient and fast moving speed. There were suspended echoes and weak echo regions on the reflectivity factor profile (RCS) map, with typical super cell characteristics.