Within a three-year cycle of studies, experiments were conducted with Polyversum WP biofungicide and Asahi SL biostimulant used as crop protection products of strawberry fruits of Kent and Senga Sengana varieties. A comparative combination was made of the following fungicides: thiram, iprodione, pyrimethanil and fenhexamid, that were applied accordingly to the strawberry protection program. All protective treatments had no significant effect on dry matter content of the fruits of both strawberry varieties and on the marketable yield in the case of Kent var. fruits. The use of combination of Asahi SL and Polyversum WP preparations resulted in increased contents of vitamin C and total sugars in fruits of Kent var. In the case of Senga Segana var., this treatment had a beneficial effect only on vitamin C content in one year of the study and on the increase in the marketable yield when coupled with synthetic fungicides. The applied crop protection products caused also sporadic changes in the contents of extract, organic acids, polyphenols, anthocyanins and antioxidative capacity of fruits of both strawberry varieties.