the objective of this study was to evaluate physiologic characteristics and oil and protein content in four soybean (glycine max (l.) merr.) cultivars (brs 133, brs 206, brs 239 and cd 202) which were harvested in four different periods (r7 stage, 7, 14 and 21 days after the first harvest stage) and produced over the growing season 2004-2005 in two sites of the mato grosso do sul state, brazil, sidrolandia (21o00？ s lat, 55o01？ w long), and dourados (22o11？ s lat, 54o55？ w long). a randomized complete block design was used in a split-plot experiment with three replicates. seeds were evaluated by means of a germination test, accelerated aging and seedling emergence on sand. oil content and protein in seed and soybean meal were also analyzed. brs 133 and brs 206 cultivars showed higher values of seed-protein, 35.67 and 35.0%, respectively, which also evidenced higher soybean meal protein content, 43.04 and 46.83%, respectively. the highest oil content was found in cv. cd 202, with a mean value of 22.63%. germination and seed vigor potentials were significantly affected by harvest periods, which presented a significant reduction when soybean harvest was delayed, such characteristics could affect the plant potential for fast growth and adequate develop of soybean plants.