In this study, a meta-analysis method was conducted to synthesize 34 existing researches by comparing the correlation of a teacher's personality traits, emotional management and leadership behavior with their classroom management effectiveness. There were 491 statistics collected from the 34 studies to be analyzed. The results obtained from the meta-analysis are as follows. In teacher's personality traits, the effective quantity of agreeableness, conscientiousness, openness to experience and extraversion reach medium levels while the effective amount of the teacher's emotional management are above medium levels. The results show that emotional management is highly correlated to the classroom management effectivess; and the older the students are,the higher the correlations are. The effective amount of the teacher's leadership behavior is above high levels, especially regarding charisma, inspirational motivation, individualized consideration and contingent reward. The effective amount of the correlations of the teacher's personality traits,emotional management, and leadership behavior with classroom management effectiveness are not significantly different among the three different education stages of elementary school, junior high school and senior high school. However, when comparing the effective amounts of the teachers ' personality traits, emotional management and leadership behavior with their classroom management effectiveness, leadership behavior is the largest, emotional management is second, and the third is personality traits. In conclusion, the teachers ' leadership behavior and emotional management can significantly enhance the effectiveness of classroom management.