Piezoelectric pumps are applied in cooling systems of microelectronic devices because of their small size. However, cooling efficiency is limited by the low flow rate. A straight arm wheeled check valve made of silica gel was proposed, which can improve the flow rate of piezoelectric pumps, solve the influence of glue aging on the sealing ability of a wheeled check valve, and reduce the size of piezoelectric pumps. This paper discusses the influence of the valve arm number (N = 2, 3, and 4), the valve arm width (W = 1.0, 1.2, and 1.4 mm), and the valve thickness (T = 0.6, 0.8, and 1.0 mm) on the flow rate characteristics of piezoelectric pumps. When valve opening rises, the flow rate increases. The simulation results show that valves with 2 valve arm number, 0.6 mm valve thickness, and 1.0 mm valve arm width have maximum valve opening. The experimental results show that piezoelectric pumps with different valve parameters have different optimal frequencies. In addition, the maximum flow rate is 431.6 ml/min at 220 V and 70 Hz. This paper provides a reference for the application of piezoelectric pumps in cooling systems.