1. A system for detecting a global harmful video, the system comprising: a video determination policy generation unit for determining harmfulness of learning video segments from video learning information to analyze occurrence information of harmful learning video segments among the learning video segments, and generating a global harmfulness determination policy based on the analyzed occurrence information; and a video determination policy execution unit for determining harmfulness of input video segments from information of an input video to analyze occurrence information of harmful input video segments among the input video segments, and determining whether the input video is harmful or not based on the analyzed occurrence information of the harmful input video segments and the generated global harmfulness determination policy.