Developing high yielding bread wheat genotypes with superior agronomic trait requires understanding the extent of genetic variability in existing germplasm. The current study was designed to generate information on genetic variability and inheritance of yield and its component traits using 36 advanced bread wheat lines. Field experiment was conducted in 2018 cropping season at Haramaya and Hirna in eastern Ethiopia using triple lattice design. Fifteen quantitative traits were measured and subjected to analysis of variance and genetic analyses. Analysis of variance revealed that there was highly significant difference among genotypes for all quantitative traits at both locations. The lowest and the highest phenotypic (PCV) and genotypic (GCV) values were obtained for hectoliter weight and number of fertile tillers per plant, respectively at both locations. Heritability in broad sense and genetic advance as percent of mean ranged from 39.1% (number of kernels per spike) to 90.1% (days to heading), and from 2.4% (hectoliter weight) to 48.5% (number of fertile tillers), respectively at Haramaya. At Hirna, these parameters ranged from 29.3% (hectoliter weight) to 91.9% (grain yield), and from 1.5% (hectoliter weight) to 27.6% (total tillers per plant), respectively. high heritability coupled with high genetic advance as percent of mean was observed for total number of tillers per plant, number of fertile tillers per plant, grain yield per hectare, and above ground biomass per hectare at Haramaya. and for spike length, total number of tiller per plant, number of fertile tiller per plant, grain yield per hectare, and above ground biomass per hectare at Hirna. This indicates that improvement of these traits through selection is easier than other traits measured.