The objective of this study was to analyze genotypic and phenotypic variability, heritability and genetic advance for grain yield and different quantitative characters using five short duration temperate maize inbred lines in a 5x5 diallel cross. High genetic advance together with high heritability for grain yield, plant height and grains per row revealed the influence of additive gene effect in determining these characters. High heritability with low genetic advance for days to 50% tasseling, days to 50% silking and cob length indicated the influence of dominant and epistatic genes for these attributes. However correlation studies showed grain yield had negative correlation with days to 50% tasseling and days to 50% silking, while positive significant correlation with plant height. Whereas positive and highly significant correlation was found with cob length, number of rows per cob and number of grains per row revealing that these are the major yield contributing traits and can help in improving maize grain yield.