Abstarct: Fluid flow modeling is one of the most widely used domains in hydraulic engineering science. Numerical modeling of flow is absolutely necessary because there are no analytical solutions for even very simple domains. The meshless method is one of the newest numerical method which has attracted much attention in recent decades. In this study the meshless local Petrov-Galerkin (MLPG) is used for fluid flow modeling. For this purpose, a MatLab code is developed. Many different types of flow including sloped channel flow, steady and unsteady flow in soils, dam break, full 2D and 3D Navier-Stokes are modeled in this study. In this method, for 2-D and 3-D analysis polar coordinates is used. Also, types of Radial Basis Function method are used for field function approximation and local integration is used to calculate the integrals. In each case numerical models were verified against analytical solutions when it existed or against finite difference method. The obtained results show the weighted residual method is one of the exact and up to date methods to obtain approximate answers in differential equations in meshless method. Comparing the results of MLPG method with analytical and other numerical methods shows that the MLPG method is highly accurate. Application of meshless local Petrov-Galerkin method in the analysis of steady and unsteady problems shows that this method has high efficiency in analyzing various hydraulic problem, independence from any background mesh and matching by boundary conditions.