In the present study, Teacher Effectiveness refers to "competencies of teachers in relation to Preparation and planning for teaching, Teacher effectiveness is the effectiveness of the teachers in their planning and preparation of lessons for teaching, classroom management, knowledge of subject, interpersonal relationship, attitude towards the children, usage of teaching aids and time management during their teaching - learning process. The present study is explored to find out the teacher effectiveness of primary school teachers in Vellore district of Tamilnadu. A sample of 260 primary school teachers selected for this study. Teacher Effectiveness Scale by Umme Dixit (1993) is used to collect the data. Results revealed that primary school teachers shows that there is no significant difference in terms of gender, area of school, medium of teaching, type of school and teaching experience. Further it shows that there is significant difference towards teaching subjects, marital status, age group and type of family of primary school teachers.