Journal of Electronic Systems MA Chunyan, JIANG Shiying3 10 2 2020 https://doi.org/10.6025/jes/2020/10/2/63-71 http://www.dline.info/jes/fulltext/v10n2/jesv10n2_2.pdf For the current lack of generation efficiency assessment of distributed photovoltaic, we construct the evaluation system from three aspects covering input, process and output. Fuzzy Mathematics and Gray System Theory are introduced to carry out quantized assessment. First, the Analytic Hierarchy Process is applied to determine the weights of various indicators, and point gradation is used to express the exact evaluation information. On this basis, the Experts Coefficient Method is used to determine the membership of the evaluation index. We establish the Fuzzy-Gray relation matrix, and use M(•, +) operator and M(􀀀, +) operator to calculate the mold propotion and gray propotion of relation matrix.To solve the problem that point gradation of the evaluation result is too large, we use the weighted average type operator M (•, ⊕) to optimize the evaluation result. Example shows that the improved Fuzzy-Gray method in the generation efficiency evaluation of distributed photovoltaic power, is good to overcome the problems that the assessment information is not clear and inaccurate. And this assessment system has certain significance for investment of distributed photovoltaic power stations and improving the power generation efficiency.