In this study, fecundity and egg size of rainbow trout (Oncorhynchus mykiss), Black Sea trout (Salmo labrax) and brook trout (Salvelinus fontinalis) were examined. Two and six years old female fish reared in commercial fish farm were used and the female size, total and relative fecundity and egg size (mm) were determined for the broodstock fish of three tested species. The average weights of broodfish of rainbow trout, Black Sea trout and brook trout 1.357.27+/-406, 532+/-673.7 and 310.40+/-85.0 g, respectively. The total fecundity (number of eggs fish(-1)) was 2.809+/-791, 1.401+/-1374 and 723+/-320, the relative fecundity (number of eggs kg(-1) fish) was 2.180+/-676, 3.558+/-1307 and 2.571+/-1530 and the egg size (mm); 4.95+/-0.2, 4.51+/-0.67 and 4.49+/-0.21 were determined for rainbow trout, Black Sea trout and brook trout, respectively. A significant linear relationship was found total fecundity and the post-stripped fish weight of Black Sea trout (r = 0.96), but this relationship was low for the rainbow trout (r = 0.28) and brook trout (r = 0.17). A negative relationship was observed between the relative fecundity and brood size in rainbow trout (r = 0.57), Black Sea trout (r = 0.58) and brook trout (r = 0.54). A significant linear relationship was observed in rainbow trout (r = 0.63), Black Sea trout (r = 0.86) and brook trout (r = 0.41) (p<0.01).