A rail-bound agricultural machinery comprises a running tire, a winding track, a scroll, a track fixed pile and a rail-bound agricultural body capable of running on the track which is unfold or winded through the movement of the running tire. A track is arranged between two height-adjustable track fixed piles which adjust the height of the track through self-adjustment. The agricultural machinery body moves freely on the track to finish farm work at different heights. The agricultural machinery has multiple functions such as sowing, fertilization, watering and spraying. The agricultural machinery only needs to be set at one time during a reason crop, which saves space, time and labor.