The process of the work function distribution modeling on the cathode surface with a real geometry is considered. As the approximating configuration an implicitly defined surface was chosen. The simulation results for the "sphere on a cone" model are presented. Database with the natural experimental results was created. Predicting the work function values for the faces with arbitrary Miller indices was carried out with the regression model. The work function assignment to a point on the cathode surface was performed by comparing normals with the different quality criteria and restrictions. For remote data processing Webbased interface was implemented. The results of the computer simulation for nickel are shown.