The field experiment with ' Cosor 5' variety of sorghum was conducted in the Central Experiment Station of UPLB starting from the third week of April 1984. The crop experienced high Rh (78 average) from flowering to seed maturity. One systemic fungicide, out of four kinds, was applied to each plot two weeks before flowering, at flowering and two weeks after flowering to control fungal infection in developing seeds. Seed dry matter accumulation, moisture content, vaibility and vigor were studied at regular intervals starting two weeks after flowering. Seed health and other characteristics were assessed at harvest and the different seed lots were stored under ambient open storape for the succeeding six months to study deterioration every month through the test of germination, AAT, GADA, MC and speed of germination. During storage, germination decreased from an initial 90 percent to 73 percent. Seedsfrom plants sprayed two weeks before, followed by at flowering consistently exhibited higher viability. On the average, a 34 percent loss in viability was observed during storage period as indicated by AAT. Significantly higher germination in AAT only during the later half of thestorage period was shown by seeds obtained from plants sprayed at theearlier two stages. Benomyl and Carboxin treatments as preharvest sprays resulted in better protection from seed-borne fungi as well as in better quality seeds on viability, vigor and storage life. Seeds obtained from the firtsstage of spraying were the in over all performace followed by those from the second spraying stage. The sprays were applied only once and the results were not consistently encouraging in all aspects, thus, it is advisable to apply the systemic fungicides more thanonce. Based on the results of this experiment, the following can be recommended for farmers, seed producers and for further studies. The residual dormancy prevalent in this variety could be over-come by treating seeds at 40 C for six days. Pre-harvest fungicides suitable againstabove mentioned fungi should be applied during the stages: two weeks before flowering (at the emergence of the ear), and at flowering.