The effect of. plant growth regulators (PGR's) on growth parameters and tuber yield in potato indicated that the growth parameters i.e., AGR, CGR, RGR and NAR increased significantly in all the growth regulator treatments in both the genotypes. Among the genotypes, Kufri Ghandramukhi exhibited higher AGR, CGR, RGR and NAR values, than HPS-II/67. Leaf area decreased in all the growth regulator treatments. With an increase in the concentration of growth retardants, there was an increase in SLW. Significantly higher tuber yield was recorded in growth retardant treated plants as compared to control and the maximum tuber yield was recorded with cycocel (1000 ppm) in both the genotypes. Kufri chandramukhi showed higher leaf area, SLW and tuber yield than HPS-II/67.