Neutral CH3radicals in a hollow cathode discharge cell containing methane have been detected with a quadrupole mass spectrometer, using the threshold ionization technique. With the experimental conditions employed in this work the measured efficiency in CH3production has been 0.2%, which is higher than that shown for other types of discharges in the bibliography. On the other hand a high depletion of the CH4density has been observed and the mass spectrum of the discharge shows the appearance of compounds atm=25, 26, and 27, proceeding from recombination processes.