The performance of Vessel Traffic Service (VTS) depends upon not only the facilities but the training and operational competence of the VTS operators. In this research, the current status and training scheme of four major VTS ports are reviewed. A fuzzy Analytic Hierarchy Process (AHP) model is subsequently developed to evaluate the training effectiveness of the VTS operators. The approach proposed enables experts to linguistically express opinions with degrees of truth of which the relationships are continuous. This solves the mapping problems between linguistic terms and discrete numerals resulting from traditional AHP methods. Four hierarchies comprising the factors of goals, competence, modules and subjects are constructed. The weights and priority of the elements for each hierarchy are acquired. The Grey Interval Measure method is also applied to analyze the training effectiveness and competence of the VTS operators by calculating the upper and lower bounds of the VTS-operator evaluations. The operational competence of VTS operators is judged by the experts invited. Finally, the interrelationships between the performance and the background indices are appreciated and the alternatives enhancing the performance of the VTS operators are identified. The measures include the recruitment of personnel with higher educational and professional backgrounds and enhancement of the professional trainings for the existing employees. The subjects of the training are also identified in this study. The contents and course hours should be appropriately organized and more attentions should be paid to the topics with higher weights. If the consistency with regard to the training schemes for the four VTS ports can be enhanced to a certain level, the quality of the VTS performance in Taiwanese waters will be increased. The marine safety will also be improved and marine environmental pollutions will be reduced.