Abstract: An experimental investigation on multi-point non-contact excitation of the bladed disc assembly models has been carried out by using electric-eddy current exciters.The simple criteria of multi-point exciting force distribution for separation into pure modes and of regulating the amplitudes and phases of exciting forces are proposed and proved （see equation 10）. Thus, it is convenient to separate the pure modes and to measure the modal parameters by means of the criteria.Some behaviours of coupled vibration of bladed discs are concluded, that is （ 1 ） The natural frequencies of coupled vibration （NFCV） rise with the increase of the number of nodal diameters of the disc, when the principal deformation of the blades is flexure and decrease a little with the increase of the number of nodal diameters of the disc if the principal deformation of the blades is torsion; （ 2 ） The NFCV decrease with the increase of the number of blades when the principal deformation of blades is flexure; however, the NFCV ascend a bit with the increase of the number blades if the principal deformation of blades is torsion; （ 3 ） When the disc vibrates with nodal diameters more than two mode shapes can be excited at a same NFCV, and the nodal lines of the disc have a phase difference only.