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 ( $2.10\pm 0.70$ g/L) and B ( $1.54\pm 0.17$ g/L) produced more biomass than the ones isolated from Location C ( $0.43\pm 0.02$ 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 ( $2.55\pm 0.74$ g/L) as compared to of commercial origin ( $1.06\pm 0.57$ g/L). Glycerol ( $2.43\pm 0.56$ g/L) was a better carbon source than glucose ( $1.84\pm 0.57$ g/L) in growth studies. Fatty acid (FA) profiles showed that the isolates from Location C (S. minutum) had low ratios of monounsaturated ( $4.21\pm 2.96\%$ ) and omega-6 ( $0.68\pm 0.59\%$ ) FAs. However, the isolates also had high ratios of docosahexaenoic acid (DHA; $35.65\pm 1.73\%$ ) and total omega-3 FAs ( $40.39\pm 2.39\%$ ), 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 ( $18.38\pm 6.27\%$ ) long chain ( $57.43\pm 8.27\%$ ) FAs.