Provided are a method, a system, and a non-transitory computer readable record medium for video quality control. A quality control method may include: receiving a video stream including frames classified into a plurality of frame types based on a reference relationship between the frames for decoding; selecting a frame type among the plurality of frame types; and controlling a quality of the video stream by multiplexing the frames included in the video stream and by outputting one or more of the frames that have the selected frame type.