To determine the nutritional quality of the lipid segment in tilapia (Orechromis niloticus) during different periods of development (alevins and juveniles), the total lipids (TL), linolenic (LNA), eicosapentaenoic (EPA), docosapentaenoic (DHA), linoleic (LA) and arachidonic (AA) acids were quantified , and the lipid nutritional quality indexes were calculated for the tilapia. The lipid profile showed that the species present high indexes of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) in both development phases. The indexes of nutritional quality of lipids, atherogenic index (AI) and thrombogenic index (TI) present low values and represent beneficial health effects, both in the alevin and juvenile fish. The quantifications of LNA, EPA, DHA, LA and AA show the greatest values (mg/g of total lipids) for the juveniles. However, regardless of the development phase in which the tilapia is, the fish may be considered a source of essential fatty acids a kind of potential and nutritional food, reflecting beneficial effects for consumer’s health.