To address the difficulty of grasping objects of various shapes and the low operational efficiency in traditional equipment, a vacuum-based robotic gripper utilizing negative pressure adsorption was designed, and its jaw mechanism was optimized. By constructing a 3D finite element model and performing dynamic simulations of the internal fluid flow within the gripper using CFD software under given boundary constraints, the flow field distribution of the internal fluid was obtained. The results indicated that the speed and negative pressure at the suction holes decreased progressively from the inside to the outside. Compared to H-type and U-type structures, the Y-type structure exhibited the highest flow velocity and negative pressure at the suction holes, making it more advantageous for workpiece adsorption. This vacuum-based gripper features a simple structure and low cost, providing a design foundation for solving grasping issues in mechanical equipment.