Due to the sensibility of soybean to the photoperiod, one of the factors that presents great impact on the seed production refers to the sowing dates. Thus, the present work had the objective to evaluate the influence of sowing dates in the agronomic traits, and in the yield components of soybean seeds, in the area of Maringá - PR. For that, were conducted five cultivars assay in the agricultural year of 1998/99, in randomized blocks design. Each assay was sowed in different dates (15/10, 30/10, 15/11, 30/11 and 15/12). The evaluated cultivars were: BRS-132, BRS-133, BRS-134, BR-16 and FT-Estrela, belonging to different maturation groups. The evaluated agronomic traits were the number of days for emergency, flowering and maturation, the height of the first pod insertion, the plant height, and the degree of the plants layering. The evaluated production components were the seed yield, the number of pods per plant and the mass of a thousand seeds. The sowing date presented influence on the number of days for flowering and maturation, reducing the culture cycle with the delay in the sowing. The average of the plants height showed direct relation with the layering degree. The crop yield decreased when the sowing
date was delayed. In all sowing dates the cultivar BRS-133 presented superior yield, while BRS134, BRS-132 and BR-16 cultivars showed intermediate performance, and the cultivar FT-Estrela, the smallest yield.