This paper proposes an automatic American football video parsing method based on transition rules of an American football game. Combining the results of live scene extraction and superimposed text detection based on image features enables us to segment the video into play units of a game. Temporally associating the segmented play units with the detected superimposed texts and the closed-caption text attaches possible semantic content information to the play units. Finally, selecting only the play units which conform to transition rules of the sports game from the obtained play unit sequence, while discarding or complementing unnecessary or insufficient play units and attached semantic content information, realizes the semantic video parsing.