A steering mechanism of an agricultural machine comprises a vehicle, two wheel fastening frames and two wheel assemblies. The two wheel fastening frames are mounted at a front end and a rear end of the bottom of the vehicle. A bearing is configured between the wheel fastening frame arranged at the front end of the vehicle and the vehicle. The two wheel assemblies are respectively configured on the two wheel fastening frames. Each of the two pneumatic cylinders is connected to one end of the wheel fastening frame and the corresponding wheel assembly. By manipulating expansion and contraction of the pneumatic cylinders to push the wheel fastening frame to rotate, the wheel assembly can be driven for steering accordingly.一種農用機之轉向機構,其包括:一車輛、二輪具固定架及二輪具組;該二輪具固定架設於該車輛底部前、後端,且位於該車輛前端之該輪具固定架與該車輛間設有一軸承,該二輪具組分設於該二輪具固定架,且設有二壓缸連接位於該車輛前端之該輪具固定架兩端與其對應的輪具組之間;藉以操作該二壓缸伸縮而推動該輪具固定架轉動,進而帶動該輪具組轉向。(11)‧‧‧底盤(12)‧‧‧軸承座(121)‧‧‧前懸吊座(122)‧‧‧後懸吊座(2)‧‧‧輪具固定架(22)‧‧‧第一端(23)‧‧‧第二端(3)‧‧‧輪具組(31)‧‧‧第一輪具(32)‧‧‧第二輪具(33)‧‧‧掣桿(4)‧‧‧第一壓缸(A1)‧‧‧安裝座
