High-speed operations up to 35 Gb/s were demonstrated for a resonant tunneling (RT) logic gate monostablebistable transition logic element (MOBILE). The test circuit consisted of a MOBILE and a DCFL-type output buffer, and it was fabricated using InP-based resonant tunneling diode/HEMT integration technology. This operation bit rate is close to the cutoff frequency of the 0.7-μm gate HEMT's used in the circuit, and was obtained after improvement of the output buffer design. This result indicates the high-speed potential of the MOBILE, though the speed is still limited by the buffer. The power dissipation of the MOBILE was also discussed based on a simple equivalent circuit model of RTD's. This revealed that the power dissipation is as small as 2 mW/gate over a wide range of operation bit rates.