The invention discloses a high-crushing-ratio double-tooth-roller crusher. The high-crushing-ratio double-tooth-roller crusher comprises a crusher shell, a first tooth roller shaft, a second tooth roller shaft, a first coupler, a second coupler, a first speed reducer, a second speed reducer, a first hydraulic coupler, a second hydraulic coupler, a first motor, a second motor, a hydraulic jack, a bolt support, a crushing beam fixing bolt, a crushing beam and lower crushing teeth, wherein a plurality of rows of roller teeth are distributed on the first tooth roller shaft at equal intervals in the axial direction; a plurality of rows of roller teeth are distributed on the second tooth roller shaft at equal intervals in the axial direction; the first tooth roller shaft and the second tooth roller shaft are arranged in the crusher shell in parallel; and the bolt support is located on the hydraulic jack and connected with an end plate of the crushing beam through the crushing beam fixing bolt. The lower crushing teeth are connected to the crushing beam. The high-crushing-ratio double-tooth-roller crusher can crush materials three times, and the crushing ratio is high; the granularity of finished products can be strictly controlled; large materials can be crushed, and the crushing efficiency is high; and falling on the whole tooth roller shafts is uniform, and the crushing capacity is high.