High initial germination values on the standard germination test neither provide a safe indication of a well stored seeds nor assure a good performance under field conditions. Degerative metabolism transformation that may occur in seeds are not evaluated by standard germination tests. Vigor tests provide better information about the storability of the seed lot. An experiment was carried out on the seed analysis laboratory of the Centro Nacional de Pesquisa de Milho e Sorgo (Nacional Maize and Sorghum Research Center), EMBRAPA, Brazil, to evaluate vigor in sorghum seeds and to compare the results with germination values attained during eighteen months in open storage. Sorghum seeds of eighteen cultivars were tested both by imersion in NH4Cl and by accelerated aging test. The results were evaluated by comparing correlations and euclidian distances between values of vigor and standard germination tests under different storage periods and indicated positive and significative correlations between standard germination and vigor seed tests with most storage periods. There was the greatest similarity or smallest euclidian distance between standard germination and imersion in NH4Cl at six months storage, while the greatest similarity between acelerated aging test and storage period was attained at fifteen months of storage.