The invention discloses a flame-suppression and explosion-suppression cryogenic liquefaction device for low-concentration coal bed gas, which comprises a coal bed gas storage system, a coal bed gas compression system, a coal bed gas purification system, a coal bed gas liquefaction and separation system, an LNG (Liquefied Natural Gas) storage system and a refrigerating circulatory system, wherein driving explosion-suppression devices are arranged on the front side and the rear side of the coal bed gas storage system; a filler used for fractionating methane in the coal bed gas and having the explosion-suppression performance is filled in a rectifying tower; the rectifying tower is internally provided with a fire-retardance and explosion-suppression material; the fire-retardance and explosion-suppression material is a fire-retardance silk screen which is laid in the filler at intervals; and the driving explosion-suppression devices can effectively prevent flame from spreading to a gas holder, and can guarantee the safety of the gas holder and an underground coal mine drainage system. The fire-retardance and explosion-suppression material is arranged in the rectifying tower, so that explosion can be prevented even if the methane enters an explosion limit range in a liquefaction extraction process of the methane, and the high-recovery and high-purity methane can be obtained from the low-concentration oxygenic coal bed gas under the condition that deoxygenation is not performed in advance.