Submerged structure leakage optical fiber positioning and orienting system and monitoring method without heat source

A submerged structure leakage optical fiber positioning and orienting system without a heat source, comprising a plurality of seepage monitoring devices connected via rotation supports; the seepage monitoring device comprises first seepage monitoring units symmetrically arranged at the front and back and second seepage monitoring units symmetrically arranged at the left and right; seepage measurement optical fibers (118) are arranged in the first seepage monitoring units and the second seepage monitoring units to monitor leakage of a submerged structure. Also disclosed is a monitoring method for the optical fiber positioning and orienting system without a heat source for submerged structure leakage. The monitoring method compares a standard optical fiber (108) and the seepage measurement optical fiber (118) to obtain the position and orientation of water seepage through flexibly arranging the seepage monitoring devices in the submerged structure; in addition, the monitoring method is easy to operate, and can acquire an accurate result.