The present disclosure discloses a method, a system, and a website server for playing a website video. The method includes: receiving a video playback request that includes a client identification and a video identification, and querying a playback record corresponding to the client identification; accumulating video playback times in the playback record to obtain current video playback times; determining advertisement information duration corresponding to the current video playback times, where the playback times are inversely proportional to the advertisement information duration; and extracting, from an advertisement information library according to the determined advertisement information duration, advertisement information that meets the duration, acquiring video data corresponding to the video identification, inserting the extracted advertisement information ahead of the video data, and transmitting the extracted advertisement information and the video data to a client for playing. The solutions of the present disclosure can improve efficiency of playing a website video.