This study was conducted to investigate the effects of Aloe vera L powder as well as Trachyspermum copticum essential oils on the shelf life of Oncorhynchus mykiss fillets during refrigerated storage. Fish fillets were treated in Trachyspermum copticum essential oil (0/1 and 0/4) and Aloe vera L powder (0/1 and 0/4) in order to achieve the best percentage of oils and powders and for each group 3 replicates were prepared. Chemical factors (pH, TVN, protein, Wet and Ash), microbial factors and sensory characteristics at days 0, 5, 10 and 15 were evaluated. In our study, significant difference were found in the pH of the treatments during increasing storage time (P> 0.05). Changes of TVN in 0/1% essential oil of Trachyspermum copticum coated fillet were less than other treatments (P< 0.05). In all treatments, fat values showed significant (P< 0.05) differences on the 1th, 5th and 10th days of study. Sensory characteristics of treatments were not acceptable on the15th day of the experiment. The results showed that live microbial communities, TBA, FFA, wet and ash were significantly affected by different levels of herbal plants (P< 0.05). Based on these results, it seems that the powders obtained from Aloe vera L and Trachyspermum copticum essential oil decrease the oxidation process and increase the shelf life of rainbow trout and can be an appropriate natural alternative to artificial preservatives