Field experiments were conducted at the New Developmental Farm, the University of Agriculture KPK Peshawar during 2013 and 2014 on macro nutrients viz., Nitrogen (N) and sulfur (S) to study their effects on phenology and physiology of different corn hybrids. The N levels were 0, 250, 300 and 350 kg ha -1 , whereas S levels were 0, 20, 40 and 60 kg ha -1 (Main plot factor), while maize hybrids were R-3305, R-2210 and R-2207 respectively, allotted to sub plots. Results showed that nitrogen level of 350 kg ha -1 significantly increased days to 50% tasseling (59) and silking (65), plant height (247 cm), leaf area and leaf area index (6664 cm 2 and 3.56), respectively, while in control plots, earlier days to 50% tasseling and silking (51 and 55), minimum plant height (192 cm), leaf area and leaf area index (4515 cm 2 and 2.40) were observed. R-2210 delayed days to 50% tasseling (56), while R-2210 delayed days to 50% silking (61). R-2207 was found with maximum plant height (232 cm), whereas in case of leaf area and leaf area index, R-2210 was found with maximum values (5570 cm 2 and 2.91). S x N and N x H had significant effect on days to 50% tasseling, whereas N x H had significant effect on days to 50% silking, plant height, leaf area and leaf area index. Sulfur had insignificant effect on phonological and physiological parameters. It is concluded that nitrogen (350 kg ha -1 ) as macro nutrient can be better exploited for improving physiological