The objective of this cross-sectional study was to establish factors influencing HIV-positive mothers to choose to use the Flash-heat (FH) method to feed milk to new-born babies in South Africa. A total of 70 HIV-positive mothers were selected using purposive sampling methods. Backward stepwise binary logistic regression analysis was carried out to establish their willingness to use the FH feeding method. More than half (54.3%) the mothers were not breastfeeding their infant and among them a third (31.6%) mentioned that breastfeeding was difficult and this was given as the reason for not breastfeeding. Most of the mothers (74.3%) reported that they would use the FH method at home as a feeding method for their infants, and most (83%) of the mothers reported that they were willing to heattreat their expressed breast milk (EBM) in a pot on a Primus stove until the water boils-as required by the FH guideline. The results showed that mothers who reported that they were willing to heat EBM at home were 24 times more likely to adopt FH compared to those who were not willing to heat EBM at home (OR=24.23, p=0.001). Also, those mothers who reported that they were willing to express milk for 4 months had 22 times more chance of adopting FH than mothers who reported that they were not willing to express for 4 months (OR=21.60, p=0.016). The findings suggest that HIV-positive mothers in a public-health facility would adopt flash-heating as an alternative infant-feeding method at home.