Potassium (K) nutrition ensures optimum yield and quality of crops. This monograph evaluates the impacts of varying levels of K on the growth, yield and K accumulation of two sunflower hybrids, viz. Hyson-33 and Hyson-39, grown at five different rates of K, i.e. 0 (control), 30 through 120 kg/ha. Across genotypes, K nutrition significantly enhanced biomass yield, number of leaves, stem diameter, head diameter, head length, head weight, achene yield and K accumulation at 120 kg K/ha, as against control. Across K nutrition, Hyson-39 had more biomass yield, number of leaves, stem diameter, head diameter, head length, head weight, and achene yield, as compared to Hyson-33. Contrarily, Hyson-33 accumulated more K than Hyson-39. In crux, adequate K nutrition enhanced the growth and achene yield of both sunflower hybrids even under adequate soil K condition, witnessing the importance of K in sunflower nutrition. Hyson-33 responded K nutrition more strongly, with comparatively lower K accumulation, as compared to Hyson-39. A dose of 120 kg K/ha was found to be the best dose in enhancing most of the growth and yield traits of sunflower hybrids.