The invention discloses a thermo-acoustic three-phase alternating current generating system driven by a double-temperature-position heat source. The thermo-acoustic three-phase alternating current generating system comprises a magnetic fluid electric generating device and a thermo-acoustic converting device forming a loop. The loop is filled with a phase-changeable work medium, the liquid phase of the phase-changeable work medium serves as the work medium of the magnetic fluid electric generating device, and the gas phase of the phase-changeable work medium serves as the medium of the thermo-acoustic converting device. The magnetic fluid electric generating device and the matched thermo-acoustic converting device serve as a loop unit, the thermo-acoustic three-phase alternating current generating system at least comprises two loop units, and the loop units are communicated with each other to share the phase-changeable work medium. A certain amount of acoustic power is produced through a gas-liquid phase change thermo-acoustic converting mechanism, and a traveling wave thermo-acoustic engine serves as an amplification stage to amplify the produced acoustic power. A medium temperature heat exchanger and a high temperature heat exchanger are different in heating temperature, the double-temperature-position heat source can be used for driving the system to work, and the utilization rate of a medium and low temperature position and low grade heat source can be increased. Gas-liquid phase change exists in the system, and therefore the self-adaptation adjusting capacity is achieved.