The invention discloses a novel hand-held hydraulic hammer, which is high pressure resistant, free of medium leakage, long in service life and high in hammering efficiency. Sealing technology that a seal ring body is extruded by a medium pressure from an inner chamber 8 of a hollow n-shaped seal ring 6 to be tightly adhered to a hammer rod 11 to realize sealing is adopted between upper and lower end covers 2 and 1 and the hammer rod 11 of a hydraulic transmission part of the hand-held hydraulic hammer. Because the inner chambers of the n-shaped seal ring 6 is hollow, the seal ring body of the n-shaped seal ring 6 of the hydraulic transmission part of the hand-held hydraulic hammer has slight friction with the hammer rod 11 and has low abrasion, and then the service life of the n-shaped seal ring 6 is prolonged; and the friction resistance between the seal ring body and the hammer rod 11 is low, so energy consumption for friction generation is low and the efficiency of hammering work is improved. The hand-held hydraulic hammer of the invention is free of medium leakage and multiply increased in the service life; a higher pressure can be borne than that of the traditional hand-held hydraulic hammer; and the efficiency of hammering work is improved.