The effect of nozzle structure of piezoelectric needleless syringes on jet velocity, turbulence intensity and jet morphology on the nozzle cross-section are studied. First, the numerical simulations with the fluid dynamic software Fluent are carried out using the Realizable k-ε turbulence model and the VOF multiphase model based on viscous incompressible fluid N-S equations. The results show that the nozzle with a cone-shaped structure can obtain a symmetrical jet with good controllability. Second, the cone-shaped contraction angle and the length of the middle cylinder of the cone-shaped nozzle are simulated and analyzed to study effects of structural parameters and their interactions on jetting speed？？and turbulence intensity of the nozzle by using the orthogonal test method. Third, the results analyzed by the SPSS software show that the cylinder length has a significant impact on the average jet velocity and mean turbulence intensity of the nozzle. The cone angle has no significant effect on the former but has a significant effect on the latter. The interaction between the cylinder length and the cone angle has no significant effect on neither the former nor the latter. When the cone angle is 30 and the middle cylinder length is 0.2 mm, the cone-shaped nozzle can obtain the best jet characteristic. The mean velocity of the outlet is 6.56 m/s and the mean value of turbulence intensity is 1.04%. This study can provide a reference for nozzle design of piezoelectric needleless syringe.