This investigation was carried out at Shandweel Research Station. Sohag Governorate in the two successive seasons of 1997/1998 and 1998/1999 to evaluate the effect of nitrogen (150.190 and 230 kg N/ fed) and potassium (48 and 96 kg K₂0/fed) on yield and quality of two sugar cane promising varieties (G. 85/37 and G. 84/47). The results showed that sugar cane variety G.85-37 attained a superiority in plant height, cane and sugar yields over G. 84-47 variety. Increasing nitrogen level up to 230 kg N/fed increased stalk height, stalk diameter, cane and sugar yields of sugar cane varieties compared with the lowest dose (150 kg N/fed). Juice purity and sugar recovery percentages were ad­versely affected by increasing the applied N-level. Applying potassium fertilizer had no significant effect on stalk height, stalk diameter, purity and sugar recovery percentages. The results showed that increasing po­tassium level from 48 to 96 K20 significantly affected cane and sugar yields in the 1st season.