The following study reports on the first thraustochytrid isolates identified from Iceland. They were collected from three different locations off the northern coast of the country (Location A, Skagaströnd; Location B, Hveravík; and Location C, Eyjafjörður). Using 18S rDNA sequence analysis, isolates from Locations A and B were identified within the Thraustochytrium kinnei species while other isolates within the Sicyoidochytrium minutum species when compared to other known strains. Cells isolated from Locations A ( 2.10 ± 0.70 g/L) and B ( 1.54 ± 0.17 g/L) produced more biomass than the ones isolated from Location C ( 0.43 ± 0.02 g/L). This study offers the first-time examination of the utility of byproducts from fisheries as a nitrogen source in media formulation for thraustochytrids. Experiments showed that isolates produced more biomass (per unit of substrate) when cultured on nitrogen of marine ( 2.55 ± 0.74 g/L) as compared to of commercial origin ( 1.06 ± 0.57 g/L). Glycerol ( 2.43 ± 0.56 g/L) was a better carbon source than glucose ( 1.84 ± 0.57 g/L) in growth studies. Fatty acid (FA) profiles showed that the isolates from Location C (S. minutum) had low ratios of monounsaturated ( 4.21 ± 2.96 % ) and omega-6 ( 0.68 ± 0.59 % ) FAs. However, the isolates also had high ratios of docosahexaenoic acid (DHA; 35.65 ± 1.73 % ) and total omega-3 FAs ( 40.39 ± 2.39 % ), indicating that they could serve as a source of marine oils for human consumption and in aquaculture feeds. The T. kinnei isolates from Location A could be used in biodiesel production due to their high ratios of monounsaturated ( 18.38 ± 6.27 % ) long chain ( 57.43 ± 8.27 % ) FAs.