The invention discloses a high-temperature-resistant bridging leaking stoppage agent applicable to lost circulation of a deep stratum and an extra-deep stratum.The leaking stoppage agent is formed by compounding, by mass, 70-80% of coke and 20-30% of fine rubber powder, wherein the coke is 4-100 meshes in particle size, and the fine rubber powder is 80-120 meshes in particle size; 0.2% of alkylphenol ethoxylates is further added so as to increase hydrophilia of the fine rubber powder and improve dispersibility in water-based drilling fluid of the fine rubber powder.Compared with a traditional bridging leaking stoppage technology, the leaking stoppage agent of coarse particles, medium-sized particles and fine particles is adopted, a dense blocking layer is formed in a stratum leakage channel through bridging, filling and blocking, losing of drilling liquid is prevented, and two types of novel leaking stoppage materials, namely the fine rubber powder and coke particles, are further adopted and compounded for leaking stoppage.The high-temperature-resistant bridging leaking stoppage agent is adjustable in grain class distribution, the coke particles are high in rigidity, compounding with the fine rubber powder is conducted, rigidity and elasticity are achieved simultaneously, density is low, the suspension property is good, and the formed blocking layer is high in compressive strength, good in compactness and capable of being resistant to the high temperature of 180DEG C.