A field experiment was carried out at The Experimental Farm of Fac. Environ. Agric. Sci., Arish University, North Sinai, Egypt, during the winter seasons of 2014-2015 and 2015-2016 to study the effect of different combinations among nitrogen, potassium and sulphur levels on growth, yield, and pungency of onion (Allium cepa L.) cv. "White Sweet Spanish" compared to control (recommended doses of N, K and S). The results indicated that application of 150% N+ 75% K₂O+ 200% S of recommended dose was the best treatment wherein increased fresh weight of leaves, bulbs and total fresh weight as well as the dry weight of the same previous parameters and photosynthetic pigments in the 1^st season. Concerning yield and its components, application of 150% N+ 75% K₂O+200% S was the best treatment for increasing the total yield and its components compared to the recommendation treatment and the other treatments. The previous treatment recorded increases of total relative yield by 131.42% and 115.77% in 1^stand 2^nd seasons, respectively compared to control treatment (recommended dose); increment in marketable yield by 130.95% and 112.08% in 1^st and 2^nd seasons, respectively; increase in relative yield of both 1^st and 2^nd grades which increased by 131.04% , 115.22% for the 1^st grade in both seasons, respectively, and by 127.89 and 111.77% for the sum of 1^st + 2^nd grades in the 1^st and 2^nd seasons, respectively, while application of 150% N+ 75%K₂O + 100% S recorded the lowest value of bulb pungency.