Background <p>Male partner involvement in family planning service is a key strategy to improve maternal and child health outcomes. Despite efforts, male participation remains a major challenge in developing countries, including Ethiopia. Therefore, this study aimed to assess male partner involvement and associated factors in family planning service utilization in Asella town, Central Ethiopia.</p> Methods <p>A community-based cross-sectional study was conducted in Asella town. A systematic random sampling technique was used to select 382 study participants. Binary logistic regression analysis was computed to identify factors associated with male partner involvement in family planning service utilization. Statistical significance was set at <i>p</i>-value &lt; 0.05 with a 95% confidence interval.</p> Results <p>The study showed that the mean age of the respondents was 41 (± 9.5 SD) years. The majority of the participants were Oromo 293 (76.7%) by ethnicity and Orthodox 198 (51.8%) by religion. The overall male partner involvement in family planning service utilization was 65.4%. Respondents who attended secondary or higher education [AOR = 3.69; 95% CI (1.89–7.16)], had five or more current children [AOR = 6.05; 95% CI (3.07–11.91)], had good knowledge of family planning [AOR = 4.58; 95% CI (2.29–9.15)], discussed family planning issues with partners [AOR = 4.47; 95% CI (1.85–13.74)], and approved the family planning use of partners [AOR = 2.74; 95% CI (1.08–7.01)] were significantly associated with male partner involvement in family planning service utilization.</p> Conclusion <p>The limited male partner involvement in family planning service utilization indicates the need for extensive efforts to achieve full participation. Enhancing community awareness, implementing educational and couple-centered interventions, and conducting qualitative research to identify barriers and facilitators are essential to improving male partner participation in family planning service utilization.</p>