Abstract: The current application of cold cathode ionization vacuum gauges in micro-vacuum systems is relatively limited. In this study, research of magnetron gauge (MMG) was conducted, which successfully achieved the goals of small size and high vacuum measurement. The volume of this MMG is only 0.3 cm³, more than 30 times smaller than currently available magnetron gauges on the market. Additionally, its connector design allows it to be compatible with standard vacuum feedthroughs. The internal electromagnetic field and electron trajectory within the vacuum gauge were modeled. The current versus pressure curves of MMG among 10⁻⁴~10⁻⁷ mbar at −500~−2500 V were obtained from the experimental tests. The most suitable voltage for MMG measurement was selected for repeated measurements and fitted to obtain its sensitivity, and the error range of MMG was obtained by comparing the fitted data with the measured data of the calibrated vacuum gauge. The results show that this MMG can accurately measure the pressure of 10⁻⁴~10⁻⁷ mbar in micro-vacuum system.