The electron‐ion recombination rate has been measured in a high‐pressure CO discharge at room temperature and at pressures from 100 to 700 Torr. The effective two‐body rate coefficient was found to be in the range 10−7−10−6cm3/sec, with an electron temperature dependence ofTe−1.6associated with the average electron energy from 0.2 to 0.7 eV. The results indicate a small pressure dependence, of less than a factor of 2, over the experimental pressure range. The principal ion at these pressures was probably the dimer,C2O2+, or a high‐order polymer ion based on ion‐molecule reactions in CO reported in the literature.