Grinding machining quality contains machining precision and grinding surface integrality. The factors influencing grinding machining quality have fuzzy characteristics. For example, the magnitude and measure methods of grinding surface roughness have fuzzy uncertainties. The grades of the machining quality are vague, and there is no definite boundary between “good” and “bad” machining quality. Analytical Hierarchy Process (AHP) combined with the fuzzy comprehensive evaluation technique is used to evaluate the grade condition of the quality in this paper. Considering the fuzziness of the factors, a two-stage fuzzy comprehensive evaluation model is proposed to evaluate the grinding machining quality. In light of different reliable degrees of different kinds of fuzzy operator models, the weighted average method is used. The membership degrees of the evaluation factors are determined by experts’ knowledge and experiences. The factor weights are calculated via the AHP method. Certain synthetic importance of each stage evaluation is presented through weighted sum of the relative important degree. Examples of conventional external grinding machining illustrate the effectiveness of the proposed model.