Abstract— This research aims to determine the effect of Atonik plant growth regulator (PGR) on the growth and yield of early maturing soybean (Glycine max L.) genotype. The study was conducted as a field experiment using polybags and employed a split plot design (SPD) with two factors. The main factor was four concentrations of Atonik PGR (Z), namely ZO (0 ml/l), Z1 (0.5 ml/l water), Z2 (1 ml/l water), and Z3 (1.5 ml/l water). The sub-factor was the soybean genotypes (G), which were G1 (GH 8 soybean line), G2 (GH 63 soybean line), G3 (GH 73 P soybean line), and G4 (Dega 1 soybean variety). The combinations of treatments were replicated three times. The observed variables included the number of leaves, the number of productive branches, the number of seeds each plant, the weight of seeds each plant, and the weight of 100 seeds. The research findings showed that the concentration of Atonik PGR at 1 ml/l water resulted in the highest number of productive branches, which is 5.25 branches, the highest number of seeds each plant, which is 55.14 seeds, and the heaviest weight of seeds each plant, which is 9.34 g. The concentration of Atonik PGR at 1.5 ml/l water produced the heaviest weight of 100 seeds, which is 23.21 g. The GH 63 soybean line produced the highest number of leaves each plant, which is 92.77 leaves, and the highest number of productive branches each plant, which is 5.25 branches. The GH 8 soybean line produced the highest number of seeds each plant, 62.16 seeds, and the heaviest weight of 100 seeds each plant, 20.49 g. The Dega 1 soybean variety produced the heaviest weight of seeds each plant, which is 9.90 g.