Afield experiment was carried out under greenhouse conditions during the winter seasons of 2013-14 and 2014-15 at The Experimental Farm of the Faculty of Environmental Agricultural Sciences, Arish University, North Sinai Governorate, Egypt. The aim of this experiment was to study the effect of different K rates (40, 60 and 80 Kg K₂O/540m²) and two sources of calcium; viz, Ca-chelate at 5g l^-1(0.5% Ca), Gurenkal at 5 ml l^-1 (0.5% Ca) as well as the control treatment (without Ca), with their interactions on growth, and yield of tomato (Solanum lycopersicon L.) hybrid V 59-48 under sandy soil conditions using drip irrigation system. A split plot design in three replicates was used. The results showed that treating tomato plants with calcium and potassium had significant and positive effects on almost studied traits of growth, and yield. The highest fresh and dry weight, as well as total yield of tomato plants were achieved when tomato plants fertilized with 80 kg K₂O/540 m² combined  with Gurenkalat 5 ml l^-1(0.5% Ca) as foliar spray followed by 80 kg K₂O/540 m² combined with Ca- chelate at 5 g l^-1(0.5% Ca).