The present investigation was conducted in the fall season of 1997, summer season of 1998 and winter season of 1998, the seeds of four new F₁ hybrids were planted in the Experimental Research Farm, Faculty of Agriculture, Minia university, in a silty clay soil.These hybrids were produced earlier in the present study by crossing Line 16 as a maternal parent with the parental lines of C1943, Ohio 7663, Saladette and Nagcarlang.  Seeds of the four new tomato F₁ hybrids and/or their transplants were treated with the antioxidant compounds, e.g. acetylsalicylic acid (ASA), ascorbic acid (AA), salicyclic acid (SA) and thiourea (Thi) at a concentration of 4 mM before planting to show the effect of these compounds on some horticultural characters e.g. mean of total yield (ton/fed), average fruit weight (g), fruit shape index, titratable acidity (%), reducing sugars (%), vitamin“C" (mg/100 g juice), total soluble solids (TSS), and seed germination percentage (%).     The obtained results indicated that hybrid “L x C" (line 16 x C1943) was the best one for average fruit weight and total yield. While, hybrid “LxS" line 16 x Saladette was the best for fruit content of reducing sugars, titratable acidity, vitamin “C" and fruit shape index. Meanwhile, hybrid “LxO" (Line 16 x Ohio 7663) was the best for TSS. Antioxidant types had insignificant effect on tomato seed germination, while hybrids and concentration of the antioxidants differed significantly in their effect on germination percentage. While, fruit weight, total yield, TSS, reducing sugars, vitamin “C" and acidity of fruits were significantly affected by seasonal changes, hybrids and antioxidant treatments. The results of the different combinations indicated that each factor was not acting dependently. Therefore, antioxidants may act differently according to the grown hybrid, and the growing season, so these factors would be considered before using any antioxidant in proper concentration to achieve its maximum effect. Using tomato hybrid and antioxidant treatment in tomato production could be good avenues to improve tomato productivity in the region of Minia, however, further studies should be done.