With persistent climate warming, a rapid increase in retrogressive thaw slump (RTS) activity has been observed in the permafrost region of the Qinghai-Tibetan Plateau (QTP). However, the initiation and growth dynamics of these RTSs have not yet been fully investigated. In this study, annual RTS observations from 2013 to 2021 within the Hoh Xil region (HXR), based on field investigations and satellite imagery interpretations, are presented. The total number and affected areas of RTSs in the HXR significantly increased during the last 8 years, and such an increase mainly occurred in 2016 when an anomalously high air temperature appeared during the thawing season, which induced the massive occurrence of active layer detachment slides. The mean headwall retreat rate of RTSs in the HXR ranged from 2.4–3.2 m/y from 2013, or their initialization, to 2021, and the highest headwall retreat occurred in the first 2–3 years after RTS initiation. In addition, the headwall retreat rate of RTSs in the study region was significantly affected by the climatic factors, including average daily air temperature, thawing degree days, and cumulative precipitation and also controlled by the ratio of slump floor slope to undisturbed terrain slope, the headwall height, and permafrost conditions. The study’s findings can serve as a reference for hazard mitigation and regional carbon cycle assessment of the QTP.