Heterosis breeding is one of the main crop improvement strategies followed in maize due to its pollination pattern which made hybrid seed production simple and commercially viable. Renewed interest in exploitation of heterosis through single cross hybrids needs information on genetic relationship and diversity existing within and among the elite breeding materials. The present study was carried out during rabi 2008 at Institute of Agricultural Sciences, BHU, Varanasi. The experimental material consists of 49 inbred lines developed at AICRP on maize were evaluated in Randomized Block Design in two replications. Analysis of variance revealed that genotype differences were highly significant for all the characters. The heritability values for various traits range from 65.28 to 99.16 % which indicates the differential influence of environment on various characters . High heritability and genetic advance as percent of mean indicated that most of the variability present in inbred lines is due to genetics and that can be exploited by simple selection.