Based on the fuzzy questionnaire, this study collected the interval data from 400 participant teachers in junior high school of New Taipei City. Teachers’ perceptions were evaluated by recognition and effectiveness of the related instruction strategies. Following the idea of fuzzy statistics, this study transformed the survey data by way of fuzzy means, defuzzification, and fuzzy distance. The findings of this study are listed as follows: 1.In positive discipline domain, high recognition and high effective methods for discipline include "Often praise students verbally", "Introduce life affairs into the classroom management", "Give awards, minor merits, major merits", and "Lead students to engage in public service activities"; 2.In general discipline domain, high recognition and high effective methods for discipline include "Inform parents co-processing" and "Adjust students’ seat"; 3.In special discipline domain, there is no high recognition and high effective methods for this discipline.