The Republic of Tanzania has been experiencing one of the highest infant and child mortality rates. There have been few efforts in understanding the bio-demographic factors associated with child loss. The 2011–2012 Tanzania HIV/AIDS and Malaria Indicator Survey is the third comprehensive survey on HIV/AIDS carried out in Tanzania. This study employed logistic regression ratios to estimate the effects of key bio-demographic variables on the outcome variable (child loss). Children who belonged to mothers with parity 4 to 8 and more than 9 had 1.27 and 1.08 times more risk of dying, respectively, compared to children in parity less than 3. Birth interval is one of the most important key factors to reduce child mortality. A birth spacing of 24 months or longer was observed in the successive birth interval of 76 % of the respondents. Special health care service fund allocation is essential to reduce child mortality in Tanzania. There is no doubt that the funding from international donor agencies and global partnerships will be important to the country’s progress toward reducing infant, child, and maternal mortality.