The data of studies on the selection and comparative assessment of the productivity of different early maturity groups of maize hybrids: ultra-early maturing - Ross 140 SV, RNIISK-1, NUR, Baikal; early maturing - Mashuk 175 MV, Mashuk 185 MV, Rodnik 180 SV, Darina MV; mid-early - Dokuchaevsky 190 SV, Krasnodar 194, Raduga, Mashuk 250 SV. All studied hybrids were distinguished by high laboratory germination capacity. Their field germination rate varied from genetic characteristics by no more than 2.1–2.8%, mainly depending on weather conditions. The features of the formation of the leaf surface, green and dry biomass, depending on the group of ripeness of the hybrids, were revealed. The maximum indicators of leaf surface formation (42.01 thousand m2), photosynthetic potential (2917 thousand m2 / ha · day) and dry biomass (9.28 t / ha) in the panicle-sweeping phase were in the mid-early hybrid Rainbow. The maximum grain yield (5.84 t / ha) was in the mid-early hybrid Raduga, which is 0.9 t / ha higher compared to the early-maturing hybrid Mashuk 185 MV and 1.16 t / ha higher than the ultra-early hybrid RNIISK- 1.