Due to significant differences in terrain and other factors, numerous morphologically intact and large-scale debris flow accumulation fans have formed along the G219 highway segment in Ritu County. In order to analyze the impact of these large debris flow accumulation fans in plateau mountainous areas on the G219 Ritu County segment and improve disaster prevention measures for debris flows along the route, field investigations, debris flow sampling, indoor analytical testing, and remote sensing interpretation were conducted. Through these efforts, the developmental characteristics and disaster-inducing mechanisms of debris flows along the G219 Ritu County segment were analyzed, and corresponding prevention models were proposed. According to the survey and research results, the debris flow accumulation fans along the G219 Ritu County segment are generally large in scale, with over 50% of them covering an area of more than 1 km². The main gullies have gentle longitudinal slopes, and the debris flows prevalent along the route are predominantly dilute. From the perspective of the accumulation fans, the hazards posed by debris flows on plateau highways are classified into three types: siltation and blocking, obstruction of the main river, and scouring and erosion. The primary hazard form of debris flows along the Ritu segment is siltation, accounting for 78% of the total. Additionally, targeted control mode are proposed based on three distinct interaction zones between the highway and the debris flow accumulation fans: the fan apex, the fan middle, and the fan edge. These measures aim to improve the hazardous conditions posed by debris flows to the highway.