PROBLEM TO BE SOLVED: To avoid reduction in both selection accuracy and grain collection efficiency due to separation wind from a rough separation fan.SOLUTION: The threshing device includes: an oscillation separation mechanism 12 sieving/separating separation targets while transferring the separation targets and a rough separation fan 14 supplying separation wind to a rough separation area of the oscillation separation mechanism 12. The oscillation separation mechanism 12 includes: a rough separation grain pan 17 a chaff sieve 21 arranged on a lower position on a transfer direction downstream side of the grain pan 17, arranged for rough separation, and capable of adjusting an opening degree and a guide plate 23 carrying down and guiding the separation targets leaked down from the chaff sieve 21 to the transfer direction downstream side. At a portion immediately before the chaff sieve 21 in the transfer direction below the grain pan 17, a distribution body 38 is arranged which divides vertically the separation wind from the fan 14 into a first separation wind blown into a first wind passage 36 between the grain pan 17 and chaff sieve 21 and a second separation wind blown into a second wind passage 37 between the chaff sieve 21 and guide plate 23. The distribution body is arranged in an inclined posture such that a distribution end side part 38B of the distribution body 38 is lowered toward the distribution end side.SELECTED DRAWING: Figure 2
