Nowadays according to expansion of industries, production of metal parts using new technologies is very important. Among the industrial equipment, shell parts due to different applications and serious challenge in forming operation has attracted the attention of many researchers. In this thesis, Incremental Sheet Metal Forming as a new process is introduced by means of which shell parts can be produced with a variety of applications. Incremental sheet metal forming has demonstrated its great potential to form complex three dimensional parts without using a matching die. The process locally deforms sheet metal using a moving tool head achieving higher forming limits than those of conventional sheet metal stamping process. The die less nature in incremental forming provides a competitive alternative for economically and effectively fabricating low volume functional sheet products. Potential application areas include aerospace industries, customized products in biomedical applications and prototyping in the automotive industry. In this special kind of forming operation, in order to decrease the force during of process and increase formability of sheet metal is used a spherical tool with small dimension. In this process, sheet metal is inserted on a punch with special shape and produced required deformation by incremental movement of tool. Therefore, creation of complicated deformations from sheet metals is achieved. In this project, based on experimental tests and theoretical analysis behavior of sheet metal in process is examined. For this purpose, by use of slab analysis, are calculated general equations of process. So, after approximating of stress field, can calculate the applied force on tools. Indeed, depending on the sheet material, thickness and etc, considerable forces can occur. Also calculation of this force is a suitable gauge for choosing kind of Computer Numerical Controlled machine. Also, determination of this parameter is necessary for prediction of critical points in process. Finite element analysis of Incremental Sheet Metal Forming is one of the important issues in this project. The importance of this issue, increases when movement of tool in an accurate path , is simulated in the software. In this case, it seems necessary definition of several thousand points of movement in software. In this thesis, by using a new method, the controlled movement of tool is modeled in ABAQUS software based on received points from the controller. According to the results obtained from finite element simulation, is provided the possibility of increasing formability of sheet metal and effective parameters in incremental forming. So, according to results of experimental tests and theoretical analysis, is presented comprehension decision about the forming mechanism in this process. Key Words: Incremental Sheet Metal Forming, Computer Numerical Controlled machine, Slab analysis, Finite element Simulation