During the agricultural year 1979-80, studies were made in Viçosa, Minas Gerais on the physiological seed qualities of the soybean cultivar 'UFV-2'. Seeds were collected at 3-day intervals for a period of 42 days beginning with the R8 stage (95% of the pods mature). Seed quality remained satisfactory for about 21 days after attainment of R8. Harvest delay resulted in the lowering of seed quality, brilliance, vigor, germination and density, and, reduced the index of resistance to seed coat shrinking. Moreover, delay in harvest caused an increased percentage of cracking and shrinking of the seed coat, and resulted in an increased damage by stink bugs. A negative correlation was found between imbibition for six hours and quality, brilliance, vigor, germination, density and the index of resistance to seed coat shrinking. A positive correlation was found between imbibition for six hours and percentage of seed coat cracking and shrinking. Imbibition for 12 and 24 hours did not give correlations among the characters studied.