The invention relates to a low-disturbance mechanical connection structure which is characterized in that a flange is made of a titanium alloy TC4 material; the flange is connected with a gear shaft by inner and outer splines; a cylindrical positioning surface I is arranged at the front part of the flange; a cylindrical positioning surface II is arranged at the rear part of the flange; the front and the rear positioning surfaces I and II are matched with the gear shaft; the excircle surface of the flange is matched with an oil seal to seal oil; two bearings are respectively arranged at the front and the rear parts of the gear shaft. The low-disturbance mechanical connection structure has the benefits that by the low-disturbance mechanical connection structure, a dynamic disturbing force generated when the gear shaft is input into and output out of the connection structure can be reduced and the problems of excessively large dynamic force and exceeding of vibration noise of a gear transmission at a high rotating speed is effectively solved.