In tribal areas of India, traditional methods of threshing of minor millets like little millet (Panicum sumatrense), M1, kodo millet (Paspalum scrobiculatum), M2, foxtail millet (Setaria italica), M3, proso millet (P. miliaceum), M4, barnyard millet (Echinochloa frumantacea), M5, finger millet (Eleusine coracana), M6 is done of beating by sticks or treading out the crop panicle under the feet of oxen. This operation is most time consuming, labour intensive, drudgery prone, uneconomical, lower output and obtain low quality products. A thresher for these millet crops was developed and optimization of the operating parameters with little millet was done by using Response surface methodology (RSM). The optimized parameters were 7.79% (d.b) moisture content, 105 kgh-1 feed rate, 625 rpm cylinder speed, 5 mm threshing sieve size which gave maximum threshing efficiency of 95.13% and cleaning efficiency of 94.12%. After optimization of parameters the thresher was tested for threshing of all the six minor millets with proper adjustments of sieve. Threshing capacity of M1, M2, M3, M4, M5 and M6 were obtained as 89, 137, 140, 91, 88 and 99 kg/h, respectively with more than 96% threshing efficiency and less than 2% broken grain.