The invention provides leaking stoppage cement paste which comprises the following components in parts by weight: 100 parts of G-grade cement, 5-20 parts of nano silica, 5-20 parts of liquid silicon, 20-30 parts of silicon powder, 5-15 parts of superfine slag, 0.5-1.5 parts of dispersing agent, 0.5-1.5 parts of retarder and 20-40 parts of water. The leaking stoppage cement paste is good in flowability, short in curing time and high in curing pressure bearing capacity; the flowability can reach 25cm; curing can be achieved after 48h at 110 DEG C; and the compressive strength can reach 127MPa. The leaking stoppage cement paste is simple, convenient and practical in preparation method, and is applicable to large-scale industrial production.