The invention relates to a transmission synchronisation method and a transmission synchronisation device for at least two transmission units (T1, T2). The synchronisation takes place in that in each case an output revolution speed (n1, n2) of an axle drive shaft arranged in a transmission (T1, T2) is adjusted by means of a first and second adjustment unit (ADU1, ADU2). The synchronisation of the first and second transmissions (T1, T2) takes place by a result value (cal_out) of an arithmetic logic unit (140) being conducted to the second adjustment unit (ADU2) arranged at the second transmission (T2), dependent on the first transmission (T1) and on the reference value (v_set) of a preselection unit (100).