Soybeans (Glycine max ) have abundant protein and lipids, making them high quality legume forage. Many factors affect yield and quality of soybean as forage, and this study investigates the effect of cultivar and sowing time on soybeans as forage in the fall crop season. To compare agronomic traits, forage yield and quality, six cultivars/lines of grain, forage and manure soybean were planted mid-month from August to October of 2017, and then harvested at the R7 (beginning of maturity) growth stage. The data show that plant height (PH), dry matter yield (DMY), crude protein yield (CPY), and content of acid- and neutral detergent fiber of forage soybean were significantly higher than that of grain soybean, but dry matter percentage of pods per plant (POD) and crude protein (CP) content were higher in grain soybean, which indicates better forage quality. With later the sowing time, there is higher POD and CP, but lower acid and neutral detergent fiber, which is good for forage quality. However, PH, DMY and CPY decreased with later sowing time. The results of fall crop season show that forage quality of forage soybean was lower than grain soybean, but its DMY and CPY were higher, providing more nutrition. In addition, the POD would be lower with early sowing time, which reduces forage quality, but increases DMY and CPY, which is ideal for forage production.