Ethiopia is one of sub Saharan African counties has been facing highest number of mother to child transmissions of HIV. Prevention of mother to child transmission (PMTCT) program plays a big role in reducing the MTCT. Nevertheless its effectiveness depends on involvement of male partners considering the fact that men are decision makers in Ethiopia families. They make important decisions that have major impact on women’s health. Male partner involvement has been seen to increase uptake of PMTCT services and their involvement underscores their importance in reducing HIV infection in children. But the program strategy is facing challenge of low male partner involvement. The purpose of this study was to examine the knowledge, attitude and practice of male partner in ANC and PMTCT services. The mixed methods design was employed in this study. A cross-sectional study was conducted using both quantitative and qualitative methods on a systematically selected 126 male partners of pregnant mothers attending in ANC clinic in Addis Ketema sub city and in-depth interviews on 6 health workers working in ANC/PMTCT service providing health institutions of the Addis ketema sub city. Data was collected in the study using questionnaire and structured interview. Methods of data analysis included descriptive statistics, correlation matrix and logistic regression analysis. The result revealed that majority of the respondents (76.2%) good knowledge about HIV, MTCT and PMTCT and majority of them (60.3%) score above the mean which shows high male involvement. Male involvement was found to have a statistically significant association with good knowledge about PMTCT (AOR= 3.0, 95%CI: 1.30-7.1), attitude (AOR=2.6, 95%CI: 1.09-6.13) and low socio-cultural factors (AOR= 5.8, 95%CI: 2.0-17.1). The level of male partner involvement was 69(60.3%). Information socio-cultural belief and male –friendly PMTCT service should be provided to the Public.