We propose semantic event detection method using MPEG-7. In the proposed method, content description technique of MPEG-7 is adopted into the detection algorithm to extract, represent, reuse, and interoperate low-level features. Also we use multiple descriptors to improve efficiency. In this paper, shots and key frames give a hint in semantic event detection by predefined inference. Each shot gets a semantic meaning using MPEG-7 descriptors with example image or image sequence. Event is detected by segmenting the shots.