The utility model relates to a nonmetal safety optical cable connector box with big capacity, which comprises a box body with an integral fastening clamping plate, an optical cable connecting frame and an optical fiber displacement sensor, wherein, the box body is a casing sealed by combining the upper part and the lower part of the casing, and the joint of the upper and the lower parts of the casing is provided with the integral fastening clamping plate which is provided with fastening holes. The upper cover is provided with a through hole, and the lower holding cover is provided with a threaded hole. Four pairs of eudipleural hollow slots are arranged on the fastening clamping plate on the joint using the threaded hole as a center. A reinforcing rib is arranged on the joint of the center line of a fastening screw and the casing surface of an outer shell to improve the integral mechanical property. The joint of the upper and the lower parts of the casing is provided with a self-adhesive strip for sealing, and the joint and the self-adhesive strip are fixed together by nylon screws. The utility model is especially suitable for the construction of optical cable communication lines in the environment of adverse natural conditions, such as alkaline land, border coastal defense, island wet land, etc., and is even more especially suitable for the construction of optical cable communication lines for military affairs and high secret grade affairs.