THIS STUDY aimed to investigate the impact of the mixture of two ascorbate salts (1:2, K-ascorbate: Ca-ascorbate, w/w) on the growth, biochemical and physiological activities and nutritive value of Pleurotus ostreatus fruiting bodies grown under salt stress. Sets of rice straw inoculated with P. ostreatus spawns were sprayed with NaCl (50mM or 100mM) and/or ascorbate mixture solution. Salinity stress reduced the fungal growth (fresh and dry weights), water content %, polysaccharides, total carbohydrate, protein, individual and total fatty acids content. On the other hand, salt stress had a negative impact on P. ostreatus accumulated defence molecules such as soluble sugars, total amino acids, antioxidant activity and total phenolics. Interestingly, the application of ascorbate salt mixture significantly improved the growth and activity of mushroom under stressed and nonstressed conditions. It enhanced the metabolism of carbohydrate, protein and lipid, activated mineral uptake and improved antioxidant defense system of stressed P. ostreatus. Together, applying ascorbate salt mixture is an environmentally friendly approach to mitigate the impact of salinity stress on P. ostreatus.