Because the pirates gathering areas, merchant shipping routes and pirates style can influence the pirates attack, the Pirate Event Special Division Algorithm based on the DBSCAN is constructed to divide the space of the pirates attack positions. A case study in East Africa is calculated and the results are analyzed, and 9 clusters are got. The analysis proves that the Pirate Event Special Division Algorithm conforms to the reality. It indicates that the method is practical and scientific. pirates attack has always been an important factor threatening international maritime transportation. Nowadays, there are numerous areas of international waters affected by pirates attack, mainly including the Gulf of Aden, Indian Ocean, the west African coast, Strait of Malacca, South China Sea and some other sea areas. Starting from the report on pirates attack geographical location, the paper established pirates attack density-based spatial clustering space division algorithm and explored the features of pirates attack events of different areas. The algorithm not only considered the geographical coordinates of the historical pirates attack events, but also the number of person being killed, missing or injured in pirates attack which can reflect the factors of pirate behavior styles.