Parallel mechanisms are widely used in various fields of engineering and industrial applications such as machine tools, flight simulators, earthquake simulators, medical equipment, etc. Parallel mechanisms are restricted to some limitations such as irregular workspace, existence of singular points and complexity of control systems which should be studied and analyzed for effective and efficient use. In this research, a new machine tool with parallel mechanism which has three translational degrees of freedom is studied and the workspace and singular points are determined by deriving analytical equations and then utilizing of Matlab software. To do so, forward and inverse kinematics of the mechanism are obtained and workspace and singular points are calculated using a search algorithm.Afterward, in order to validate the results, the proposed mechanism is simulated in automatic dynamics analysis of mechanical systems(ADAMS) software. Moreover, in order to investigate the quality of robot performance and dexterity of the mechanism in its workspace,global dexterity index(GDI) of the robot is calculated using Jacobean matrix at different positions of the mobile platform. Parallel mechanisms are widely used in various fields of engineering and industrial applications such as machine tools, flight simulators, earthquake simulators, medical equipment, etc. Parallel mechanisms are restricted to some limitations such as irregular workspaces, existence of singular points and complexity of control systems which this should be studied and analyzed for effective and efficient use. In this research, a new machine tool with parallel mechanism which has three translational degrees of freedom is studied and the workspace and singular points are determined by deriving analytical equations and then utilizing of Matlab software To do so, forward and inverse kinematics of the mechanism are obtained and workspace and singular points are calculated using a search algorithm. Afterward, in order to validate the results, the proposed mechanism is simulated in automatic dynamics analysis of mechanical systems (ADAMS) software. Moreover, in order to investigate the quality of robot performance and dexterity of the mechanism in its workspace, global dexterity index (GDI) of the robot is calculated using Jacobean matrix at different positions of the mobile platform.