The local geological conditions are strong weathered, strong unloading anti-dip thin layer-middle-thick layer sand slate with joints and fractures developing, broken surrounding rocks, open fissures and serious loose unloading in road slope excavation at Lianghekou hydropower station. The frame beams and non-cohesive steel strand dispersion-type pre-stressed anchorage cable were designed to reinforce the side slope. The paper describes the super grouting control technique for pre-stressed anchor grouting in poor geological conditions.