Embodiments of the present invention discloses a method and an apparatus for evaluating video quality, which relate to the field of communications technologies, and are invented for improving accuracy of evaluating quality of an IPTV service. The method includes: acquiring a channel video stream; acquiring a decoding feature parameter of a decoder, where the decoding feature parameter at least includes a decoding buffer capacity; acquiring a frame information loss ratio according to the decoding feature parameter, and acquiring mean opinion score-video MOS-V parameters according to the channel video stream; and acquiring a MOS-V value of the channel video stream according to the frame information loss ratio and the MOS-V parameters. The embodiments of the present invention are mainly applied to a technology for evaluating video quality.