1. A system for tracking a moving object, the system comprising processing circuitry configured to at least: acquire a plurality of frames in time series; detect a plurality of moving objects from the frames; correspond each of the moving objects among the frames, and extract a tracklet of each moving object corresponded; store the tracklet of each moving object corresponded; set a frame to calculate a position of a moving object to a notice frame; group the frames into a first block including at least the notice frame, a second block positioned before the first block in time series, and a third block positioned after the first block in time series; acquire a secondary tracklet included in the second block, and correspond the secondary tracklet with tracklets included in the first block and the third block, based on a similarity between the secondary tracklet and each of the tracklets; and associate the secondary tracklet with the corresponded tracklets, as a tertiary tracklet.