This study was carried out at the Experimental Farm and Laboratory, Faculty of Agriculture, Sohag University, Sohag, Egypt during two successive winter seasons, 2011/2012 and 2012/2013 to investigate the effect of spraying micronutrients and potassium fertilization on the characteristics of storage ability of three cultivars of onion (Improved Giza 6, Giza 20 and Shandaweel 1) grown under Sohag Province conditions. Three times of foliar trace elements application (control "without foliar", once, twice and three times) and four rates of potassium fertilizer (Zero, 52.5, 105 and 157.5 kg feddan , one feddan = 0.42 ha) were used in this study. 1 The new Duncan’s multiple range tests showed that themost storage studied characters were affected significantly by foliar application with trace elements, where the lowest decay % were obtained from three timesfoliar application with trace elements on Giza 20 and Shandaweel 1 cultivars in both seasons and only in the first season on Improved Giza 6 cultivar. Moreover, some storage studied characters were affected significantly by potassium fertilizer, where the highest potassium rate (150 kg K O feddan ) produced the 2 1 lowest sprouting % on Giza 20 cultivar in both seasons. In addition, the most storage studied characters were affected significantly by storage methods, where the lowest sprouting %, decay % and weight loss % were obtained from plastic nets bags in all cultivars. Some storage studied characters were significantly affected by some interactions among factors under studies. The interaction among trace elements application, potassium fertilizer rate and storage methods, had no significant influence decay % on all cultivars in both seasons. The interaction among trace elements application, potassium fertilizer rate and storage methods, had a significant influence sprouting %, weight loss % on Shandaweel 1 cultivar in both seasons and only in the first season, respectively