Abstract: the study method of millimeter three-ports element oscillator stabilized with a dielectric resonator is presented. The original structure of loop-feedback is used. In the project (Ka-band HEMT oscillator), the integrated microstrip circuit is used, the high-electron-mobility-transistor microwave monolithic integrated circuit is applied and the cylindrical dielectric oscillator is used, not only as a frequency-stabilizing element, but also as a feedback circuit coupled to the O/I of the MMIC. The phasenoise and output power of the oscillator is measured.Experiment results is indicated that this method can be used in millimeter system.