The existing grading evaluation system of Carya cathayensis is not suitable for the development of Carya cathayensis market in China. In this paper, a new grading standard and evaluation system (GSES) is proposed for Carya cathayensis classification problem based on fuzz rules. The proposed scheme consists of three levels, namely, target layer, factor evaluation layer and further refinement layer. Finally, the proposed method is applied into the evaluation for Carya cathayensis of three different brands, and the results are satisfactory. Compared with the conventional method, the proposed scheme is effective and reasonable for the evaluation of Carya cathayensis.