To improve the flow rate of the valveless piezoelectric pump with semi-cylinder bluff-bodies, combined with the unequal flow resistance characteristic of conical cavity, a valveless piezoelectric pump with semi-cylinder bluff-bodies in a conical cavity was designed in this paper, and the theoretical formula of its flow rate was established. The flow velocity distribution of pump cavity was simulated numerically. The resistance characteristics of this pump and the valveless piezoelectric pump with semi-cylinder bluff-bodies were compared. The simulation results show that the valveless piezoelectric pump with semi-cylinder bluff-bodies in a conical cavity can achieve unidirectional fluid transportation, and its transportation capacity is better than that of the valveless piezoelectric pump with semi-cylinder bluff-bodies. The prototypes of two pumps were made, and the flow rate and pressure difference tests were conducted. The experimental results show that under 220 V driving voltage, the maximum flow rate and pressure difference of the valveless piezoelectric pump with semi-cylinder bluff-bodies in a conical cavity are 30.96 g/min and 394 Pa, respectively. Compared with the valveless piezoelectric pump with semi-cylinder bluff-bodies, both the flow rate and pressure difference have been improved.