Education plays a vital role in society, and the use of Mother Tongue-Based Multilingual Education (MTB-MLE) as a medium of instruction has been proven to enhance learners’ comprehension and engagement; however, its recent removal has raised concerns about its effects on teaching and learning. Thus, the main objective of the study was to determine the significant relationship between the level of teachers' perception on the removal of mother tongue as a medium of instruction and the learners' engagement among Key Stage 1 teachers in Inabanga South District. Specifically, it aimed to determine the profile of the respondents in terms of age, sex, and years of teaching experience. The design used by the thesis writers was the descriptive survey method with the aid of a researcher-made and adopted questionnaire. The data gathered were statistically analyzed and interpreted using percentage, weighted mean, standard deviation, Chi-Square, and Pearson Product-Moment Correlation Coefficient (PPMCC). Based on the findings, most of the respondents were female teachers aged 40 - 45 years old with 8-10 years of teaching experience. It was found out that the teachers had a low level of perception on the removal of mother tongue as a medium of instruction, while learners' engagement in terms of emotional and behavioral aspects was found to be high. In addition, there is no significant difference between the level of perception among key stage 1 teachers and level of perception of the teachers on learners’ engagement when grouped according to teachers’ profile. Moreover, there was no significant relationship between the level of perception on the removal of the mother tongue and the learners' engagement. The thesis writers concluded that language policy changes may not directly affect learners' engagement but can influence classroom inclusivity and teaching practices. Finally, future thesis writers are recommended to conduct further studies that include both teachers' and learners' perspectives to gain a more comprehensive understanding of the effects of language use on engagement.