The quality of spillway excavation has an important influence on the safety of the later project operation.Based on the rock mass excavation of an unlined spillway of Namkong 1 Hydropower Station in Laos,different blasting excavation techniques were proposed and adopted for four key parts.The field excavation results show that the deep hole pre-splitting blasting technique can well solve the problem of excavation shaping control of spillway high slope.The profile is clearly visible after blast with the half hole ratio and the maximum fluctuation meeting the design requirements.In addition,the energy dissipation-accumulation control blasting technique has been successfully applied in the stilling basin floor excavation,which has achieved good excavation shaping effect and greatly accelerated the construction progress.For the excavation of the special part of the tail of the stilling basin,the deep-hole pre-splitting one-time excavation shaping technique is adopted for the upstream and downstream surface,while the horizontal pre-splitting and vertical hole contour excavation technique is adopted for the top horizontal surface,which can solve the excavation shaping control problem of shaping of the tail sill.For the small bench blasting area with the requirements of excavation quality,such as the drop sill section of gate chamber,the blasting technique of small diameter and small bench is preferred than that of large diameter and small bench.