The present disclosure relates to a transmission of an agricultural vehicle, the transmission including: a forward shift unit for performing shift with respect to drive transmitted from an engine of an agricultural vehicle; a clutch unit connected to the forward shift unit so as to selectively output drive transmitted from the forward shift unit; an adjustment unit connected to the clutch unit; and a backward shift unit connected to the adjustment unit so as to perform shift with respect to drive transmitted from the adjustment unit. The adjustment unit includes: a first adjustment mechanism connected to a first clutch mechanism included in the clutch unit; a second adjustment mechanism connected to a second clutch mechanism included in the clutch unit; and an integration mechanism connected to both the first adjustment mechanism and the second adjustment mechanism. The backward shift unit includes one backward shift mechanism connected to the integration mechanism.