The utility model provides a media separating mechanism contains separation roller train and reversal roller train. Same rotation direction rotation all face to separation roller train and reversal roller train. The reversal roller train pressurizes many media on the separation roller train to prevent the media near the reversal roller train to pass through the passageway between separation roller train and the reversal roller train, and permission and separation roller train direct contact's media pass through the passageway. The reversal roller train contains axis body, two reversal gyro wheel and cyclic annular components. Two reversal gyro wheels are installed on the axis body to it is rotatory to receive the axis body drive. Cyclic annular component is installed on the axis body, is located between the two reversal gyro wheels, can rotate for the axis body to can be for the radial movement of axis body along the axis body, these media are suppressed jointly to cyclic annular component and reversal gyro wheel. A formula scanning apparatus of feeding also provides in the lump of using above -mentioned media separating mechanism.