The purpose of the present research was to study the field performance of soybean seeds proceeded from crops established at different planting dates. Two experiments were grown under field condition, in Botucatu, São Paulo State, Brazil, on a soil classified as Ultisol (?Terra Rosa Estruturada?). The seeds of the three cultivars (?Paraná?, ?Santa Rosa? and ?UFV-1?) studied originated from crops of the previous year (1977/78 and 1978/79), that were planted fortnightly in six planting times, since October. The number of seeds sowed in the row were the same in all treatments. The characteristics evaluated were: seedling emergence (%), initial and final number of plants/m, cultural cycle, plant height, first pod msertion height, yield components and grain yield. In the early maturing ?Paraná? cultivar, the seeds from the earlier planting dates showed a low percentage of seedling emergence, which resulted in poor stand. The plant characteristics of cv. ?Paraná?, including yield, were affected when the differences in stands were large. In the other two cultivars that effect was not observed.