Background: The third United Nations Sustainable Development Goal includes a commitment to end HIV. In lined with the Sustainable Development Goal, Option B+ programs hold great promise for preventing transmission of HIV and moving towards an “AIDS-free generation. However, an estimated 110,000 AIDS-related deaths occurred among children in 2015. The Global Plan also identified Ethiopia as one of 22 high priority countries for improved prevention of mother to child HIV transmission services. But, there is a scarcity of data on the contributors of loss to follow up and mortality after option B+ guideline implementation in the Amhara regional state, Ethiopia. Methods: This study conducted in five zones of the Amhara regional state, Ethiopia. The study considers mothers that admitted to the 5-referral hospitals’ PMTCT departments, midwifery professionals who work in the respective hospital’s PMTCT departments, and HIV officers. The period for data collection was from March 21 to May 18/2019. An in-depth qualitative interview employed to gain access to the participants’ experiences and conducted an inductive qualitative content analysis.Results: Mothers, health professionals, and HIV officers were asked about the contributors of lost to follow up in the Amhara region. The participants’ suggestions on the causes categorized into a health facility, stigma and discrimination, and socioeconomic status themes. On the prevention of loss to follow up, the views of study participants were categorized into health facility improvement, psychosocial support, and loss to follow up retention mechanisms. On the causes of HIV related mortality, participants’ views categorized into vertical HIV transmission, carelessness of parents, and poor socioeconomic status themes. In the recommendations to prevent loss to follow up and mortality, participants forwarded their suggestions for health facilities and professionals and civic societies. On the prevention of mortality, participants’ views categorized into health care and mothers’ awareness.Conclusions: The participants were emphasizing the health facilities, health care professionals, and awareness of families to prevent loss to follow up and mortality among exposed infants after admission to the PMTCT program. Hence, concerned bodies mainly minister of health should outline on improving the service provided in the PMTCT department.