The theories and methodologies of the source identification and the sound field reconstruction of broadband fan noise will be studied, which is the dominant sources of turbofan on aircrafts. The parametric equivalent source model of unsteady aerodynamic loading will be established, the inverse sound propagation relationship in the non-uniform flow will be constructed, and the regularization method based on the Bayes’ theory will be developed. Additionally, the transfer function from the duct propagation modes to radiation modes will be studied in both solid and liner ducts. The spinning modes will be detected in the compressed mode space. And the fan noise filtering algorithms will be researched based on the cyclostationary theory. Finally, the methodologies for the source identification and the sound field reconstruction will be built. Experiments will be conducted in the anechoic chamber, as well as in the anechoic open wind tunnel with a turbo compressor, to validate the proposed theories and methodologies. The methodologies can be used to test the results of theoretical researches and numerical calculations of broadband fan noise, offer the input of aerodynamic loading to blade designs, and validate the effectiveness of noise reduction.