A study has been made of the reaction of NO and CO on industrial heterogeneous oxide catalysts STK, nickel-chromium and NTK-10-1. Their high activity at temperatures of 300-475 degrees C has been shown. The influence of the reaction medium on reduction has been established: maximum nitric oxide conversion (similar to 90%) is observed in a reducing atmosphere with CO/O-2 > 2. It was found that the selectivities of catalysts STK and Ir/Al2O3 in the reduction of nitric oxide by carbon monoxide are similar.