The electron density profile has been analysed using the maximum entropy method (MEM) in signal processing of the X-mode microwave reflectometry carried out in the GAMMA 10 tandem mirror. Although the detected reflectometry signals included the noise components due to density fluctuations in addition to signal components, the signal components were spectrally separated from the noise components using MEM. Reconstructed density profiles are consistent with that obtained from the millimetre wave interferometry measurements assuming a parabolic profile. The present MEM analysis will also be applicable to microwave reflectometry experiments on tokamaks or stellarators where signal levels were significantly affected by plasma movement or density perturbations.