The invention discloses a submarine cable protection apparatus. The submarine cable protection apparatus comprises a protection pipe arranged on a cable in a sleeving manner; the protection pipe is sleeved with two arc-shaped locking blocks; a first locking block and a second locking block which are arranged symmetrically are fixedly mounted on each arc-shaped locking block; the first locking block is positioned above the second locking block; a movable groove is formed in the bottom of the first locking block; the same fixed plate is fixedly mounted on the two side inner walls of the movablegroove; a movable rod is glidingly mounted on the fixed plate; a fixed block is fixedly mounted at the bottom of the movable rod; and the top of the fixed block is in contact with the bottom of the fixed plate. By virtue of the submarine cable protection apparatus, effective protection on the cable can be provided, and the protection pipe can be mounted and fixed conveniently, and the positions ofthe arc-shaped locking blocks can be adjusted conveniently, thereby adapting protection pipes of different lengths; and by protecting the protection pipe by a first protective pipe and a second protective pipe on each arc-shaped locking block conveniently, the overall protection performance is improved, and the submarine cable protection apparatus is simple in structure and convenient to use.