Abstarct: In this study, the effect of whey coating containing dill (Anethum graveolens L.) essential oil nanoliposome on the physicochemical, microbiological and sensory characteristics of rainbow trout (Oncorhynchus mykiss) was investigated. Treatments include: control without coating, coating containing whey, coating containing whey with essential oil (whey-EO) and coating containing whey with nano EO (whey-NEO). The particle size, polydispersity index, zeta potential and the encapsulation efficiency were ranged from 142 to 159 nm, 0.79 to 0.88 Mw/Mn, -16.3 mV to -11.7 mV and 45.85-70.01%, respectively. Microbial analysis, after 21 days, the maximum and minimum of total viable counts (TVC), total psychrophilic counts (TPC) and lactic acid bacteria (LAB) counts were related to control (8.16 for TVC, 8.46 for TPC and 7.7 log CFU/g for LAB) and whey+NEO (7 for TVC, 7.3 for TPC and 6.16 log CFU/g for LAB), respectively. Also, results of pH, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and total volatile baxse-nitrogen (TVB-N) after 21 days were ranged from 6.3 (whey-NEO) to 7.5 (control), from 11.5(whey-NEO) to 20.9 mEq/Kg (control), from 5.23(whey-NEO) to 8.34 mg MDA/kg (control) and from 22.5 (whey-NEO) to 37 mg N/100 g (control), respectively. The highest and lowest of DPPH radical scavenging were detected, in the BHT 200 (95.2±2.5) and EO 50% (43.7±1.25), respectively and the nanoliposome form of dill essential oil showed better antioxidant activity than the free form of dill essential oil. Finally, in all sensory evaluation items (texture, off-odor, discoloration and red color), the best result after 21 days was related to whey-NEO (score=1). Consequently, the edible coating containing whey-baxsed nanoliposome of EO could be effective to the preservation of fish's microbiological, physicochemical, and sensory characteristics.