In this project is a study of grid generation by adaptive mesh. Form the problems solving of partial differential equations by finite difference methods. Normally of calculation is a use regular rectangular mesh but regular mesh has many limitation because when the shape of calculation domain is irregular, there will cause inconsistency between the boundaries of the discrete domain and the physical domain. therefor, grid generation by adaptive mesh is a useful in numerical methods for solving partial differential equations and is interesting the study include applying to the generation of a computational mesh in a region of physical domain cover the upper Gulf of Thailand.