To study the effect of some fungicides invitro on an isolate of the fungus Cladosporium fulvum(cook) that causes leaf mold on tomatoes, five fungicides were tested Flint - Topsin-M- Score and Collisand Indofil-M at concentrations between 1 - 4000 ppm. The results showed that Score and Indofil-M were the most effective fungicides inhibiting hyphal growth for the isolate even at 10ppm. Also, they inhibited completely the spores germinatios at the 100 ppm. The effects of fungicides Flint and Collis were weak on hyphal growth of the isolate and inhibited almost completely the spores germinatios at 1000 ppm. We didn,t observe clear inhibiting effects of Topsin-M on hyphal on the growth of the spores germinatios at 1000 ppm .