Abstract:I present an optimum fitting solution of wave equation, which is an accurate numerical solution of wave equation that is different from difference solution. A new discretization method is proposed by analysing difference discretization method. The new discretization method derives a fitting equation from the overall fitting of a partial differential equation whereas difference discretization method forms difference equation by performing difference approximation of each partial differential term in the equation. The difference approximation is called the partial discretization method, and the overall fitting the overall discretization method. Illustration analysis shows that this optimum fitting method applies to various difference migration methods and has the advantage of difference method and higher image accuracy, and that its fitting factor is adaptable to variations of multiple parameters such as sample, velocity, step size and so on. The new method is handy and easy to form different operation schemes.