The magnetron cavity was developed for use in the rubidium atomic frequency standards, through which the main characteristics of the magnetron cavity were studied, mainly including the resonant frequency, quality factor, oscillation mode. The results show that the resonant frequency of the magnetron cavity can be attenuated to 6.835 GHz, which is the resonant frequency for rubidium atoms, and Q-factor can be attenuated to 600～1000, the oscillation mode is typical TE011 mode which is needed for the rubidium atomic frequency standard, and the cavity has a lower frequency temperature coefficient (32.5～35.0 kHz/℃), therefore these derivative magnetron cavities can meet the requirements for rubidium atomic frequency standards well.