This project was about the effect of mother tongue (L1) on the English subject outcome in secondary schools in Uganda from selected schools in Kanyum sub county, Kumi District. Questionnaires were designed and used to get secondary data; where by respondents were required to answer the questions. The researcher conducted face to face interviews with students and teachers on issues pertaining the influence of mother tongue (L1) on English Subject outcome in secondary schools from selected schools in Kanyum Sub County. A number of languages had been advanced about the need for a second language. In the context of this study, English was the language stressed mostly. English was a language which was widely spread and in Uganda it was the major medium of communication and instruction in a classroom situation with an exception of the Thematic Curriculum. David (1997) in his encyclopedia of language said that; children learn to speak in a popular view by copying the utterances heard around them and by having correct responses strengthened by the repetitions, corrections and other reactions that adults provide.