Objective To study the relationship between the viscoelastic polymer parameters of non-newtonian fluid and the data obtained during the process of inkjet droplet formation. And to composite the droplet type spaces with the variable parameters through numerical processing. Methods In the simulation experiment, the FENE-CR fluid model was adopted, and the constitutive equation of the FENE - CR fluid model was combined with Navier-Stokes equation and continuum mechanics to deduce the relationship between the fluid viscoelasticity and the polymer fluid parameters. The droplet spray model was established, and the 3D numerical simulation method was used to simulate the impact of polymer parameter changes on the inkjet droplet formation process. Results Through the numerical simulation method we got the relationship between the polymer parameters (polymer ductility L, polymer concentration C and polymer De value) and the main data such as the main droplet final velocity vf, droplet size V, the tail maximum length Z and the tail first breakage time tb in the process of the inkjet printing drops formation. Conclusion For non-Newtonian viscoelastic fluids, although the proportion of polymer in the fluid was very low, its impact on the changes of fluid viscoelasticity was significant. The different type and concentration of polymer led to dramatic changes in the values of the final droplets formation process.