Two field experiments were carried out at El-Bramoon Agricultural Research farm of Mansoura Horticultural Research station, during the two successive summer seasons of 2011 and 2012 on sweet potato (Ipomoea batatas, L.) plants cv.  Beauregard. The aim of this study was to study the effect of foliar spray of calcium at (0, 1000 and 2000 ppm), potassium fertilization at (0, 48, 72 kg K₂O/fed.), and foliar spray of antioxidants (control, ascorbic acid at 200 ppm and salicylic acid at 200 ppm) on plant growth, yield and its components as well as tuber root characters. The obtained results showed that foliar spray of only 2000 ppm of calcium or with the interaction among 1000 ppm of calcium, potassium fertilization at 72 kg K₂O/fed. and foliar spray of antioxidants as ascorbic acid at 200 ppm or salicylic acid at 200 ppm recorded the highest values of the above-cited indices compared with the control. Positive interaction between foliar spray of calcium and potassium fertilization and foliar spray of antioxidants were often observed. The best results were obtained by foliar spray of only 2000 ppm of calcium or with the interaction among 1000 ppm of calcium, potassium fertilization at 72 kg K₂O/fed. and foliar spray of antioxidants as ascorbic acid at 200 ppm or salicylic acid at 200 ppm.