Abstract: Teff has the largest value in terms of both production and consumption in Ethiopia and the value of the commercial surplus of teff is second next to coffee. The traditional way of threshing and winnowing, leads to contamination of grains with foreign matter (pebbles, dirt, and cow dung) and loss of grains due to the foreign matter dropping in to grains and the wind blowing grains away with chaff. This design helps to find out the typical dimensions of various components of the threshing machine with great accuracy in small time and also gives fine representation of engine drive teff threshing machine. The machine was fabricated by using the low cost material available in local market. Main components of this machine are: frame, sieve, and threshing unit, concave, blower, feeding table, sucker, and grain delivery chute and engine seat. A teff threshing machine was designed, constructed and evaluated for its performance. Mild steel was used majorly for the fabrication of component parts for ease of machining, assembling, maintenance and affordability. The machine was evaluated on farm observed to acceptable threshing capacity and efficiency and the operation cost and quality loss due to traditional threshing were minimized by far.Abstract: Teff has the largest value in terms of both production and consumption in Ethiopia and the value of the commercial surplus of teff is second next to coffee. The traditional way of threshing and winnowing, leads to contamination of grains with foreign matter (pebbles, dirt, and cow dung) and loss of grains due to the foreign matter dropping in to gr...Show More