This study examined the effects of pronunciation on English language performance among
students in public secondary schools in Webuye East Sub-county, Bungoma County.Guided by
the three objectives, the research sought to assess how pronunciation influences students'
performance in written English and oral tasks,to explore the role of mother tongue Interference in
pronunciation and to evaluate the effectiveness of teaching strategies used to improve
pronunciation.The Communication Competence Theory by Dell Hymes(1972) formed the basis of
the theoretical framework.The study adopted the descriptive survey design. The target population
was formed by form two and three students, and teachers of English language.Stratified and simple
random sampling methods were employed to sample schools and student respondents respectively,
while purposive and simple random sampled teacher respondents.The study utilized questionnaires
to collect data and it was analyzed using a Statistical Package for Social Sciences (SPSS) version
21software.The findings of this study established that mispronunciation negatively affects
students' academic outcomes by lowering students' grades in both written examinations and oral
assessments. Majority of the teachers also affirmed that many students also misspell words due to
incorrect pronunciation, which further reduces their confidence in English speaking tasks. The
findings further revealed that mother tongue interference significantly contribute to pronunciation
difficulties. Direct translation from native languages often leads to substitution of English sounds
and grammatical errors. In addition, the study found that pronunciation errors are rarely corrected
in class and there is limited use of technological tools or audio aids to support pronunciation
practice. While interactive strategies such as debates and group activities provide some
improvement,the lack of adequate teaching materials and consistent corrective feedback weakens
the effectiveness of pronunciation instruction.The study concludes that pronunciation plays a
crucial role in students' English language performance and recommends increased teacher
intervention, the ministry of education and school administrators to provide enough and
appropriate teaching resources for pronunciation and adoption of modern teaching strategies to
enhance students' pronunciation and confidence