The invention discloses a management and maintenance method for prolonging service life of an orthotropic deck slab steel box girder bridge. The management and maintenance method relates to the field of bridge management and maintenance. The management and maintenance method comprises the steps of determining the anticipated remaining service life of a steel box girder of a to-be-tested bridge, selecting the testing section of the to-be-tested bridge; determining fatigue vulnerable points in the testing section of the to-be-tested steel box girder, selecting at least nine fatigue vulnerable points as testing points, mounting a strain sensor on each testing point; mounting strain data of all testing points when a vehicle passes by through all strain sensors for no less than seven days, and calculating the remaining service life of each measuring point according to the strain data; and respectively determining the remaining service life of a left early-warning testing point and a right early-warning testing point are smaller than the anticipated remaining service life of the to-be-tested bridge, and taking a corresponding maintenance method. The management and maintenance method has advantages of relatively low repairing cost and relatively short construction time. Furthermore the service life of the bridge can be prolonged.