The influences of grafting treatments (6001 and Star rootstocks in addition to, check nongrafted transplants) and some foliar spray treatments (potassium silicate at rate 4 and 5 ml/L, calcium at rate 1 and 2 ml/L and check) on growth, yield and fruit quality of watermelon cv. Aswan F1 were investigated. The experiment was conducted in Baloza Research Station, Desert Research Center, at North Sinai Governorate during the two successive growing seasons of 2016 and 2017. The results indicated that plants sprayed with potassium silicate at a rate 5 ml/L or grafted onto Star rootstock recorded the highest significant values on transplant stand (success) percentage, vegetative growth characteristics (plant length, fresh and dry weight), yield and its components (fruit weight, fruit size, rind and flesh thickness and total yield), while the lowest values were observed in check nongrafted plants. Meanwhile, grafting had reducing effect on fruit quality, where the highest values of total soluble solids and total sugars were found in the fruits of nongrafted plants. The application of 5 ml/L potassium silicate gave the best significant values of TSS and total sugars compared with check treatment during the two studied seasons.