The present study aimed to investigate the effect of essential oils (EO) (thyme and rosemary) on the quality of marinated rainbow trout during storage at 4ºC. Three different treatment were tested: C1; (control samples), C2; (marinating with 1% [v/w] rosemary EO added) and C3 (marinating with 1% [v/w] thyme EO added). Fillets were subjected to microbiological (total aerobic mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria, yeast and mould), chemical (pH, thiobarbituric acid reactive substances-TBARS, total volatile base nitrogen-TVB-N) analyses and sensory quality testing throughout the storage period. Difference in microbiological and chemical changes between samples was found to be significant (p<0.05) during storage period. In conclusion, essential oils treatment to marinated had positive effect on shelf life rainbow trout, especially thyme oil showed more positive effect when compared with rosemary oil.