Abstract <p>The article presents the results of mathematical modeling of plasma transport in a spiral open magnetic SMOLA trap. The mathematical model is based on an elliptical equation in a cylindrical coordinate system for the density of a substance. This equation is derived from the MHD system of equations, taking into account the spiral geometry and the stationary stage of the matter transfer process. The coefficients at which the qualitative correspondence of the plasma density distribution to experimental data is achieved are determined. As a result of the comparison of calculated and experimental data, a refinement of the existing estimate of the diffusion coefficient was made. This result will make it possible to use the developed mathematical model at the design stage to predict the parameters of plasma confinement in traps with a spiral magnetic field.</p>