Abstract: Truancy is deliberate absence from school on the part of learners without the knowledge and consent of parents. The aim of this study was to establish the factors that contribute to student’s absenteeism and their effects in secondary schools in Meru South District, Kenya. Pilot study was done in three schools from the neighboring Maara district. The study collected views from principals, class teachers, counseling teachers and form two students, purposive and stratified random sampling method was used to select a sample size 298 students 8 Principal 8 counseling teachers and 8 class teachers. Questionnaire was used to collect data. Data was analyzed quantitatively using statistical package for social sciences (SPSS) version 11.5 for windows and presented using frequency distribution table, bar charts and percentages. The study found that unsupportive school culture; family, social economic and psychological factors significantly contributed to truancy. The effects of truancy were identified as poor academic performance for the truants, their class and school the school, wastage of learning time, dropping out of school, poverty to the individual and family in future, involvement with delinquent behavior, family instability, social maladjustment and insecurity in the family. The study recommended that education managers hold regular meetings with principals and teachers to sensitize them on truancy and discuss ways of dealing with truancy in their schools.