Abstarct: The Isogeometric analysis (IA) method is baxsed on Computer Aided Design (CAD). The main advantages of the isogeometric analysis are: a considerable reduction in the size of system of equations, accuracy in the definition of the geometry and its boundaries, using of common methods in finite element (FE) method, having more advantages over FE method, the possibility of solution of problems with moving meshes such as Lagrangian problems, etc. In this thesis, it is tried to use this method for solution of Eulerian and Lagrangian problems in computational fluid dynamics due to its novelty. For this purpose, two types of Eulerian problems are modeled by IA method. The first problem is to find the velocity distribution of uniform flow in a sloped channel and the second is irrotational flow around circular and rectangular obstacles. Also in Lagrangian approach two problems of incompressible free surface flows and dam break are simulated. The purpose of modeling velocity distribution of uniform flow in a sloped channel is to compare IA and FE method by size of system of equations. The purpose of modeling irrotational flow around circular obstacle is to investigate the ability of the IA method in constructing curves and surfaces with high precision. The purpose of modeling dam break is to investigate the ability of the IA method in some problems with large deformations which usually happens in Lagrangian approach.