In the feasibility study stage of highway engineering construction project, it is one of the bases for compiling investment estimation to reasonably estimate the quantity of subgrade works. Combined with years of practical work, this paper introduces the contents and compilation methods of subgrade works in the feasibility study stage of Highway Engineering in mountainous and hilly areas. Taking 11 specific projects as examples, this paper analyzes the specific application of empirical analysis method, and concludes that the empirical analysis method can be applied to the estimation of highway subgrade engineering quantity in mountainous areas in the feasibility study stage