An incommensurate magnetic structure with the propagation vector k = [0 0 1/2-δ ] was found in the compound 160Gd2BaCuO5 below 12 K by powder neutron diffraction. The ”lock-in” to the commensurate structure with k = [0 0 1/2] was observed at 5 K, accompanied by the spin-orientation in the Gd subsystem and structural magnetostriction transition. Similar to others rare-earth cuprates the compound Gd2BaCuO5 shows a low-dimensional magnetic behaviour.