The instability of a twodimensional thin panel in subsonic flow was studied by using Differential Quadrature Method (DQ method). The eigenvalue numeric method was used to study the instability characteristics of panels with differential boundary conditions. The results show: 1) that the critical parameters can be efficiently obtained by DQ method;2) that panel which is fixed at both ends undergoes divergence;3) that the clampedspring support panel flutters,4) and that the critical flutter dynamic pressure is influenced by some system parameters.