A video service quality assessment method and apparatus are provided to resolve a prior-art problem of relatively low accuracy of an assessment result. A monitoring device obtains an identifier of a to-be-monitored channel, an identifier of to-be-monitored user equipment, and configuration information of a video service transmission system; obtains a multicast video stream of the to-be-monitored channel based on the identifier of the to-be-monitored channel; obtains a retransmitted video stream based on the identifier of the to-be-monitored channel, the identifier of the to-be-monitored user equipment, and the configuration information of the video service transmission system; determines a to-be-assessed video stream based on the multicast video stream and the retransmitted video stream; and parses the to-be-assessed video stream, and obtains an assessment result based on a parsing result and the configuration information of the video service transmission system.