History and Government enhances development of learners’ international consciousness and their appreciation of different cultures. Students’ performance in the subject in Kenyan secondary schools and in particular, Kericho County has been unsatisfactory thus raising concerns about their learning and understanding of the subject. Teaching approaches and the way they are perceived by teachers and learners have been associated with students’ academic performance. This study investigated teachers’ and learners’ perceptions on the effectiveness of Field-Based Study Approach (FBSA) to enhance deep learning of the subject in secondary schools in Kericho County. Descriptive survey research design was adopted. The target population comprised all History and Government teachers and learners in public secondary schools in the County. The study’s accessible population was 274 teachers and 7,575 form four students. Stratified, proportionate and simple random sampling techniques were used to select 163 teachers and 433 form four students who participated in the study. Data was collected using Teachers’ Perceptions Questionnaire (TPQ) and Learners’ Perceptions Questionnaires (LPQ). The instruments were validated by five experts in the Department of Curriculum, Instruction and Educational Management of Egerton University. The two instruments were pilot tested and their reliability coefficients deemed reliable at 0.926 and 0.856 respectively since they were above the 0.70 threshold. Data were analysed with the aid of Statistical Package for Social Sciences (SPSS) version 22. The results indicated that the teachers’ and learners’ perceptions on effectiveness of FBSA in deep learning were positive. The findings of the study may provide History and Government teachers with an insight of the effectiveness of FBSA, leading to frequent use of the approach. This may enhance students learning and understanding of the subject and thus improve their academic performance in it.