An appreciation of how large-scale magnetic fields can be maintained in the subsolar Venus ionosphere by the solar wind interaction was previously obtained with one-dimensional diffusion/convection numerical models. Here, the solution of the diffusion/convection or dynamo equation for the ionospheric field is generalized to three dimensions under the assumption that the field and flow at the upper boundary (in the magnetic barrier) is known from a previous gas dynamic model, and that the ionospheric plasma velocity is known. The latter is given by the combination of the antisunward convection inferred from measurements, and the downward drift calculated from the observed vertical thermal pressure gradient. The results suggest that the low-altitude magnetosheath field draping may be distorted by the interaction with the ionosphere in such a manner that there is an apparent ''focusing'' of the field toward the subsolar point. Although the model resolution is too course to resolve the magnetic ''belt,'' an ionospheric field is produced that is strongest and parallel to the overlying field in the subsolar region, as is observed.