The plants of two strawberry varieties ‘Fortuna and Festival’ were inoculated with two isolates of Verticillium dahliae ‘VFF and VDS’, isolated from strawberry fields lacated in the Gharb region (Morocco). The monitoring of the symptoms evolution of the Verticillium wilt, in fuction of time, on the inoculated plants has allowed to note different types of symptoms: Early yellowing followed by necrosis, stunting, wilting and death of plants especially in plants of the Fortuna variety. Calculated severity indices and the coefficients of infection, seven days after inoculation of strawberry plants are respectively about 13.5 and 11.5%. After four weeks, they reached respectively 66 and 86% for plants of the variety 'Fortuna' and 31.45 and 44.62% for those of variety 'Festival'. After six weeks, the severity indices and the coefficient of infection are respectively 77.44 and 106.8% in the 'Fortuna' plants inoculated with 'VFF' isolate. Comparisons between indices of severity and coefficients infection in inoculated plants of both varieties have shown that this is the variety 'Fortuna' which is most sensitive to isolate 'VFF', which showed pathogen also against the 'Festival' variety. Both tested isolates 'VFF and VFS' were re-isolated from all levels of plants: roots, collars and leaf petioles.