In order to analyze the response regularity of the organic sulfur structure in coal to microwave and understand the microwave sulfur removal mechanism furtherly, the change rule and bond broken characteristics of the sulfur bond in several typical sulfur model compounds in coal were studied under the different external energy fields using the density functional theory simulation. The results show that the molecular activity and polarity increase with the electric field increasing. The bond lengths of S-S and C-S in molecular increase with the electric field heightening, the resonance frequency of each group decreases with the increase of applied electric field, and the vibration spectrum intensity also changes. It needs to consider the changing influence of the molecular activity and polarity of the organic sulfur structure in coal which the external electron fields lead to during the microwave desulfurization process.