For future estimating of potential limitation of some terrestrial consumers by food quality in global scale, the water-land fluxes of essential polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA), with the biomass of emergent aquatic insects in several biomes were estimated. The water /land area ratios for each biome were calculated by dividing the water area of each biome by its terrestrial area. Data on insect emergence from water bodies (g of dry mass m-2 year-1), were generalized and averaged for each biome.From available data, EPA and DHA contents (mg g-1 dry mass), in the biomass of emergent aquatic insects were calculated first so that annual fluxes of PUFA to land area via aquatic insect emergence could be estimated for each biome. A high variability of PUFA fluxes occurred between the biomes, ranging from 0.04 to 4.39 mg•m-2 •year-1. In this study, the aquatic PUFA supply to land area appeared to be significantly lower than that of a previous global average estimate. This finding indicates that a putative limitation of some terrestrial consumers by food quality, namely by the supply of aquatic PUFA, may be more severe than was previously determined.