The invention relates to an impact-rotary-type hole-bottom freezing wire-line coring drilling tool and method for natural gas hydrate, and belongs to the technical field of geological core drilling. The coring drilling tool is composed of an inner pipe assembly and an outer pipe assembly, the inner pipe assembly comprises a salvage mechanism, an elastic clip positioning mechanism, a suspension mechanism, a single-action mechanism, a buffer mechanism, an impact mechanism and a hole-bottom freezing mechanism. According to the coring method, a natural gas hydrate core is frozen by adopting a refrigerating unit to circle a refrigerant, rapid freezing can be achieved, the freezing effect is good, compared with a traditional refrigeration mechanism, recycling of the refrigerant is uniform in refrigeration, and the cost and auxiliary operation time caused by the supplementary of the refrigerant can be reduced effectively; and the inner pipe assembly does not rotate in the drilling progress, so that damage of the mechanical force caused by the rotation of the drilling tool to the natural gas hydrate core is avoided, moreover, due to the advanced drilling of an inner pipe, the erosion of the natural gas hydrate core by flushing fluid is avoided effectively, and the core recovery rate, integrity and representativeness of the natural gas hydrate core are improved more effectively.