Jinyang-Ningnan segment of Yibin-Panzhihua highway, with a total length of more than 100 km, is located in the reservoir area of the newly constructed and being constructed giant hydropower stations. Reservoir bank reformation has a significant impact on the highway project. However, there is no similar engineering experience that can be referred to as we investigate the effects of reservoir bank reformation along such ultra-long highway under complex conditions. In this paper, we first of all examined and classified the factors affecting bank reformation. Such factors include landform, formation lithology, geological structure, bank slope structure, and hydro-meteorology. Subsequently, we assessed the stability of bank slope along the highway by qualitative and quantitative means. Furthermore, we revealed the control factors, development characteristics and laws of hazards during reservoir bank reformation via correlation analysis.Results suggest that lithology is the dominant controlling factor of reservoir bank reformation; impoundment has evident imapct on the stability of reservoir bank slope; large-scale landslide mainly develops in the bedding slope of soft rock. The research finding offers support for the planning and design of the studied highway project, and also a reference for similar projects in future.