The 2.5-D quasi-cylindrical method has been proposed recently for simulation of 2.5-D case. The remarkable

advantage of the quasi-cylindrical approach over the common cylindrical approach is that it can deal with non

rotationally symmetric situation, aiming at broadening this range of application. In addition, for largesized surveys

the quasi-cylindrical approach is very efficient as compared with the conventional 2.5-D methods. In this paper, the

authors have developed an implementation of this approach which is based on quasi-cylindrical acoustic wave equation,

using the higher-order staggered finitedifference method. With some numerical examples including axisymmetric and

non-axisymmetric models, this paper demonstrates the validity and feasibility of the authors' approach.