Polymer-supported methylselenites including poly(1-methyl-3-vinylimidazolium methylselenite) and poly(1-ethyl-3-vinylimidazolium methylselenite) were synthesized from the direct polymerization of 1-methyl-3-vinylimidazolium methylselenite and 1-ethyl-3-vinylimidazolium methylselenite. The results of Fourier Transform Infrared (FT-IR) spectra and thermogravimetric analysis (TGA) clearly showed that methylselenite is tightly immobilized on the imidazolium-based polymer. These polymer-supported heterogeneous catalysts exhibited reasonably high activity for the oxidative carbonylation of aniline under experimental conditions. The catalyst recycle test showed that the supported catalyst can be reused at least up to five times with a moderate loss of activity. (C) 2007 Elsevier B.V. All rights reserved.