The invention discloses a transformer station regulation and control data interaction synthesis information quality processing method. The method comprises the following steps: step one, splitting information quality participating in synthesis calculation into independent sub quality; step two, determining whether the type which the sub quality belongs to is two-state quality or a three-state quality; step three, according to the computation type which the synthesis calculation belongs to, obtaining a sub quality calculation result by use of a corresponding quality synthesis rule; step four, obtaining total quality, i.e., quality of synthesis information by performing "bitwise OR" on the sub quality calculation result; and step five, taking the quality of the synthesis information as signal quality of an input source for mapping to telemetering data quality. According to the invention, the problem can be solved that a regulation and control master station cannot realize refined research and determination of the operation condition of power grid equipment through full utilization of transformer station basic data quality bits due to unreasonable processing of regulation and control data interaction synthesis information, and the regulation and control master station can be better supported in realizing safe and reliable operation of a transformer station.