For ranking and comparing different design results of the channel width given by different codes to promote the reasonable design of channel width, comprehensive evaluation indices are determined from the point of navigation safety and efficiency after analyzing and comparing three different kinds of channel width design codes. The entropy weight-TOPSIS-grey correlation comprehensive assessment model is built, in which, the objective weight of each index is obtained from the entropy method. The positive & negative grey correlation grade between alternative schemes and positive & negative ideal solution are calculated respectively, and the grey correlation relative closeness between each alternative and ideal solution is obtained. So the scheme ranking and optimization can be achieved based on the relative closeness. Given practical assessment situation, three different kinds of design codes are taken into practical example analysis and assessment. Then, from the view of navigation safety, navigation efficiency and comprehensive benefit, the reasonability of the channel width given by different codes for the given situation is clarified. The assessment result tallies with the actual situation and can provide the basis for further study and development for the channel width design code.