In order to evaluate the overall level of the development of intelligent technology and its role in promoting the economic benefits brought to the smart grid，a generalized production function model improved by the principal component analysis（PCA）theory is proposed.The model can decorrelate and reduce the dimensions of the multivariate evaluation indicators of the elements of the input and output.Then using the reconstructed multiple comprehensive evaluation indicators of principal components to measure the development level of intelligent technology based on the generalized production function model.Solve the intelligent rate of technological progress and its contribution to revenue by the Solow residual method，and estimate the tendency to smart technology progress according to Hicks definition.Finally，plan out a flow chart of the smart technology assessment.Related examples have verified the correctness and feasibility of the evaluation method.