D.Cur. / The feeding of low birth weight babies remains a challenge. Mother's milk is deficient in protein, calcium, magnesium and phosphate. These elements need to be supplemented in order for the low birth weight baby to grow under optimal conditions. The objective of the study was to compare the growth of the low birth weight baby, who was only fed mothers milk, to the low birth weight babay who was fed mother's milk with a commercial fortifier, using mass, lenght and head circumference as a guide. The literature study has shown that there are different methods which can be used to compliment the deficiencies in mothers's milk, for example: premature milk formula, alternating mother's milk with premature milk formula, additional additives to mother's milk and commercial fortifiers. Previous research of mother's milk fortifiers has shown that the biochemistry has positvely influenced their growth. Six patients were used in the experimental group and received 25% mother's milk and 75% fortifier. The control group consisted of eight babies who only received mother's milk. All the babies met the criteria and reached the 1600 gram weight by the time the study was completed. The Mann Whitney U test was used to calculate the results. No significant statistical growth was seen in any of the areas tested. It was concluded that mother's milk should be fortified, despite the results of the study, as mother's milk is definitely deficient in certain nutrients. It is possible to use mother's milk fortifiers in a stronger consentration.