As was suggested by a theoretical study made by one of us [An. Fis. 93 (1997) 105] the attenuation of a N2O supersonic beam was observed when molecules interact with both a homogeneous electric field and a radiofrequency resonant with the Stark N2O(1, +/-1) --> (1, 0) transition. The experimental observation of the new phenomenon opens interesting possibilities not only for fundamental research but also for technological applications, as for example the development of new analytical techniques based on such a molecular beam depletion.