This paper presents the results of the first experiments demonstrating the possibility of wireless data transmission using a subterahertz band gyrotron signal as a carrier. The output power of the subterahertz gyrotron was modulated by a rapid change in the potential of the currentless anode. The resulting amplitude modulated (AM) signal with the medium power of about 50 W was received by the ultrafast THz detector. Successful transmission of an analog sound signal and transmission of a digital signal at a rate up to 1.5 Mbps over a distance of about 2 m was demonstrated. The investigated approach confirms its potential for data transmission using gyrotron in any frequency band without loss of generality.