In the present study, strawberry (Fragaria× ananassa Duch.) plants c.v. Festival, were grown in a local farm (Meet Kenana, Toukh county, Qaliobia governorate, Egypt) during the two-winter successive seasons of 2020 and 2021. The effect of pre-harvest spraying with different biological control agents on postharvest decay and quality of strawberry fruits under storage conditions was investigated. Postharvest decay caused by Botrytis cinerea (grey mold) and Rhizopus stolonifer (soft rot) is the most important factor affecting strawberry fruits in the field, during harvest transportation and storage. The plants were pre-harvest sprayed with some biological control agents; Bacillus subtilis, Bacillus megatherium, Trichoderma album and Trichoderma asperellum (T34), Trichoderma viride, compared to Switch (synthetic fungicide) and tap water as control treatment. All biological control agents showed the highest linear growth inhibition of fruit rots pathogens under laboratory conditions. The tested treatments gave the best effects as they decreased the disease incidence (D.I.) of fruit rots in the field. The fruits were harvested at a commercial maturity 3/4 color stage and stored at 0 °C and 95-98 % RH for 20 days. The obtained results indicated that pre-harvest spraying of strawberry fruits with Trichoderma asperellum (T34) was the most effective treatment for delaying fruit deterioration throughout reducing color changing, decay maintaining good appearance, firmness, acidity, TSS% and weight loss.