In this paper, a novel three-port combiner based on coaxial cavity is presented, which consists of a band-pass filter with a transmission zero and a ultra-wideband band-stop filter, and the combiner is different to the conventional combiner based on microstrip or stripline. The design and simulated results show that the novel combiner has a good performance, which are insert loss more than -0.5dB and return loss less than -20dB between the GSM/DCS/TD band (800-2170MHz) and WLAN band (2400-2500MHz), the isolation in both bands less than -85dB, respectively. In addition, the performances of the novel combiner are demonstrated experimentally, the measured results have good agreement with simulated results.