A bell-shaped mountain was used to study the influence of the topographic parameters on the amplitude of the lee wave.The theoretical analysis showed that,if the topographic height remains constant,the lee-wave amplitude attains its greatest value when the topographic half-width is suitably the reciprocalof the wave frequency.If the topographic height and half-width vary by different proportions,the variety of wave amplitude is uncertain.Especially,if the topographic height and half-width vary by the same proportion,i.e.the topographic preserves its shape,the maximum amplitude occurs when the half-width is the double reciprocal of the wave frequency.Then,the sensitivity tests were performed to examine the change of topographic parameters by the ARPS model,which are consistent with theoretical results.