This work was carried out to determine the effect of a plant growth regulator on fruiting of tomato plant, Lycopersicum esculentum Mill. cv. Miguel Pereira. In this trial, 3-CP (3-chlorophenoxypropionic acid) was applied at 25, 50, 100 and 200 ppm. It was verified that treatment with 3-CP did not affect fructification and number of aborted flowers, but 3-CP 200 ppm reduced the total number of flowers and increased the percentage of parthenocarpic fruits.