The teacher is most essential in the education field and he/she is the most important pillar in the development of schooling. Teaching aptitude of teacher is a significant issue in teaching and learning progress. The purpose of the study was to find out the relationship between teacher effectiveness and teaching aptitude of teachers. The sample comprised one hundred secondary school teachers working in secondary schools of Bangalore South District selecting by simple random sampling technique. The Teaching Aptitude Scale developed by Dahiya and Singh (2004) and Teacher Effectiveness Scale (2006) developed & standardized by Umme Kulsum was utilized for data processing. The Pearson?s Product Moment Coefficient of Correlation, ?t? and F Test statistical procedures were applied to examine the formulated hypotheses. The correlation result shows significant relationship between Teacher Effectiveness and Teaching Aptitude of secondary school teachers and from ?t? and ?F? test statistical procedures gender and type of school management factors were influences on Effectiveness in Teaching. The female teachers had higher effectiveness in teaching than male teachers and private unaided school teachers had more effective when compared with teachers from private aided and government schools. The study suggests that there should be further focal point on developing aptitude skills among teachers through well supervised practices to improve their teacher effectiveness.