This study was conducted to describe factors explaining the low involvement of male partners in the PMTCT service in the Bunia health zone. The cross-sectional method, supported by a questionnaire survey, was used to conduct this study among 400 male partners of pregnant women in the Bunia health zone in August and September 2021. Content analysis supported by percentage calculations was used to analyze the data. After analysis, the study revealed the following: - The main factors associated with the low involvement of male partners in accompanying their wives to the PMTCT service are respectively the perception of poor organization of PMTCT services (73%), lack of time on the part of spouses (48%), ignorance of the importance of PMTCT by spouses (36.75%) and the PMTCT service being perceived as a female environment (21%). - Nearly 2/3 of respondents mentioned that non-participation in the PMTCT service could result in remaining sero-ignorant (36.68%) and increase the risk of contamination (29.65%). In the light of these results, it must be admitted that efforts still need to be made to ensure the effective involvement of male partners in PMTCT services. An important aspect is to develop strategies to overcome the main factors affecting the non-involvement of male partners in PMTCT services.