African yam bean is a legume that has not been sufficiently utilized. In order to encourage large scale cultivation of this crop, a threshing machine was designed, fabricated and evaluated. The materials for the machine parts were carefully selected from locally available materials putting into consideration factors such as strength, ergonomics, quality of grain and cost using relevant engineering principles. The machine was locally fabricated having a capacity 38.96kg/hr. The results of evaluation indicated a mean threshing efficiency of 99.5%. The damaged grains were 11.41% of the threshed grains and a cleaning efficiency of 95.42% was recorded. The efficiency of the thresher was observed to vary with the moisture content of the grain. This variation persist until the optimum moisture content is reached.
