The main objective of this thesis is to study what was the interaction between the navy and pirates after the Opium War. The relationship between pirates and navy are not just navy destroy pirates and pirates hide from navy. In fact, When pirates were powerful than navy, navy would attempt to recruit them. When navy were much more powerful than pirates, navy would destroy them, In the dissertation, the author tried to use the official documents such as Grand Council File Copies of Memorials and Imperially rescripted Palace Memorials as my primary sources. The relation between navy and pirates were changes when navy equipped with new equipment, the author would draw an comparison on the situation in navy before they equipped steamships and after. In Chapter Two, the author tried to focus on pirate Bu Xingyou——a typical case of pirates to research the interaction between navy and pirates. In Chapter Three, the author tried to research on how navy in Guangdong equipped with steamship to destroy pirates. In Chapter Four, the author was attempted to research on the interaction between navy and pirates after more steamships were equipped in navy. In Chapter Five, the author was tried to research how did navy in Guangdong destroy pirates after most steamships were dismissed.