The study examined the contribution of parental involvement and support in pupils' learning activities to the improvement of academic performance in government primary schools in Buyinja Sub-county. Parental involvement was measured through homework support, provision of learning materials, and school participation. A cross-sectional survey design was adopted, and data were collected from 473 respondents comprising pupils, parents, and teachers. Structured questionnaires and interview guides served as data collection instruments. Results revealed a statistically significant positive relationship between parental involvement indicators and pupils' academic performance. Pupils whose parents actively supported their learning at home and participated in school activities consistently attained higher academic grades. The study concluded that parental involvement was a strong and consistent contributor to improved academic performance in government primary schools in Buyinja Sub-county. It was recommended that schools and local governments establish structured parental engagement frameworks to systematically harness the academic benefits of parental involvement.