A traffic density analysis method includes decoding encoded video data corresponding to an analysis region to obtain a decoded video signal and code information, determining a moving object in units of a macroblock on the basis of the decoded video signal, the code information and a previously decoded video signal, analyzing a macroblock determined as the moving object, setting a specific region in a screen using an analysis result of the macroblock, and estimating a traffic density in the analysis region from information related to the moving object passing through the specific region.