A steam-injection boiler flue gas leakage stopping device comprises a corrugated pipe (1), a heat insulating material (2) and a pipeline (3). The steam-injection boiler flue gas leakage stopping device is characterized in that the pipeline (3) of the steam-injection boiler flue gas leakage stopping device penetrates the center of the corrugated pipe (1), two ends of the corrugated pipe (1) are welded with the pipeline (3) to form a sealed cavity, and the heat insulating material (2) wraps the corrugated pipe (1). The steam-injection boiler flue gas leakage stopping device is applicable to steam-injection boiler flue gas leakage stopping of oil field heat and solves the problems that a gap is generated on a joint part of the boiler pipeline and a boiler body as the boiler pipeline deforms due to expansion with heat and contraction with cold and boiler vibration and high-temperature flue gas of the boiler leaks, potential safety hazards are eliminated, heat loss of the boiler is decreased, energy consumption is reduced, and the efficiency of the boiler is improved.