This study was able to determine magnitude of male partner involvement into PMTCT services as well as identifying factors affecting male partner involvement into PMTCT services as perceived by mothers. Furthermore it has demonstrated that male partner involvement has a significant influence on preventing Gender based violence. The magnitude of male partner involvement shown in this study was 24.7%. This findings correlates with that reported by Byamugisha et all in Uganda where 26% of men whose wives were attending ANC at Mbale Regional Referral hospital reported to have full male involvement . Likewise, the magnitude of male involvement in this study is more or less the same as that reported in the bottleneck analysis report of Tanzania e-MTCT of 2012 which showed only 21% male partner involvement , this slight difference might be attributed to under reporting of the routine data used to compile the bottleneck report. However due to differences in definition of male involvement and setting of the study, the magnitude in this study is much higher from 12.5% which was reported by Msuya SE et al in Moshi urban . Studies done in Cameroon, South Africa and Malawi have reported male involvement of less than 20% [23–25]. In the same way as found by Kilewo C. et al in 2001 among women participating in a perinatal trial in Dar es salaam, less than 20% of them had shared their HIV results with their partners eighteen months after diagnosis . This correlates with the findings of this study where the proportion of HIV positive pregnant mothers who have shared their serostatus to their partners was 37%. This could be contributed by low (38%) HIV testing level of male partners as noted also by Falnes EF et al 2010 in northern Tanzania . Tadesse E et al 2004 in Blantyre Malawi found also that women have great trust to their male partners if and only if they are tested for HIV because majority of them choose their partner as their primary confidants after they tested for HIV .