An experiment on maize germplasm was conducted during Spring, 2005 at Maize and Millets Research Institute, Yusafwala, Sahiwal under irrigated and drought stress conditions (half irrigations than irrigated ones i.e. missing alternate irrigation). Highly significant differences were present among genotypes for days to 50 percent tasseling, days to 50 percent silking, plant height, cob height, flag leaf area, number of rows per cob, number of grains per cob, biomass per plant and grain yield per plant under both conditions except 1000-grain weight, which was only significant under drought conditions. Grain yield per plant was strongly associated with days to 50 percent tasseling, days to 50 percent silking, 1000-grain weight and biomass per plant under irrigated conditions. A strong association was also found between grain yield per plant and days to 50 percent tasseling, days to 50 percent silking, plant height, cob height, flag leaf area and biomass per plant under drought conditions. Plant height showed maximum positive direct effect on grain yield followed by number of rows per cob and cob height so these traits may be given more emphasis for selecting high yielding maize genotypes under irrigated conditions. However, under drought stress conditions, days to 50 percent silking had maximum direct effect on grain yield followed by cob height and flag leaf area. Hence these characters will be considered for yield improvement under drought conditions.