The invention discloses a non-destructive inspection method for the comprehensive quality of food and a device thereof, wherein image information reflecting characteristics of an inspected object, such as color, texture, size and shape, etc. is acquired by a machine vision system, and spectral information reflecting physical and chemical indexes of the sample such as moisture, sugar, protein, lipid and PH value, etc. is obtained by a spectrographic detection system, and the acquired image information and the spectral information undergo the preprocessing on the data layer and the information integration on the characteristic layer or the decision layer; together with a built food classification grading expert system, the quality of the inspection object is comprehensively graded. The invention comprehensively utilizes the light image information and the spectral information to inspect the appearance and inner quality of food, thereby the invention can make a quick, convenient, non-destructive and objective inspection on the comprehensive quality of food; the method and the device are widely used to classify food materials, monitor the food processing and grade the food, etc., which ensures the quality of food and contributes to the good quality and low price of food.