The invention discloses a baffle grouting construction method for water leakage plugging of a shield in-out hole. The baffle grouting construction method comprises the steps that 1, a baffle groove isformed, specifically, the baffle groove used for mounting a water-stopping baffle is formed in the inner side of a water leakage portal of a constructed shield tunnel; 2, the water-stopping baffle ismounted, specifically, the water-stopping baffle is mounted in the baffle groove; 3, gaps are filled, specifically, the gaps between the front side of the water-stopping baffle and the baffle grooveas well as between the rear side of the water-stopping baffle and the baffle groove are filled correspondingly; 4, grouting holes are formed, specifically, the grouting holes are drilled from the bottom of the inner sides of segment rings from top to bottom; and 5, grouting is conducted, specifically, plugging slurry is injected into a stratum at the bottom of the constructed shield tunnel throughgrouting equipment to plug a water leakage area. The baffle grouting construction method is simple in step, reasonable in design and good in use effect, the water-stopping baffle is arranged on the inner side of the portal, thus the injected plugging slurry remains in a gap between a segmental lining and the stratum at the bottom of tunnel, accordingly a seepage channel in the water leakage areais effectively plugged, and the problem of water leakage plugging of the portal is solved completely.