Abstract: Genetic analysis of yield and quality characters in spring wheat was studied in seven cultivars and their F1s obtained from a diallel cross without reciprocals at Bangladesh Agricultural University, Mymensingh. Graphical analysis revealed the presence of epistasis for the characters plant height, spikes per plant, spike length, grains per spike, 1000-grains weight, grain yield per plant and protein content. Partial dominance was showed by the characters days to maturity, plant height, grains per spike, 1000-grains weight and protein content. On the other hand the characters spikes per plant and spike length were controlled by over dominance. Among these gene actions partial dominance could easily be exploited through conventional breeding.