The fifth Harry Potter book is to go on sale in China 10 days early in an effort beat pirates.
The English version went on sale in June
But unofficial copies of Harry Potter and the Order of the Phoenix appeared on the internet just weeks after the book was released in English.
The People's Literature Publishing House of China said 800,000 translated copies would go on sale from Sunday.
Pirated copies, often badly translated, have left publishers fearing legitimate sales could be hit.
Harry Potter and the Order Phoenix became the biggest-selling book of the year when it was released in English in June.
But many countries have had to wait for translated editions, leading people to attempt to unofficially translate the English version into other languages including German, Spanish and Chinese.
People's Publishing House editor Liu Yushan said attempts were being made to crack down on pirates.
"We welcome readers to actively report any copyright violations
or illegal activity and if the report is verified we will offer a reward," he said.
"We are asking all the media to step up supervision efforts and
report all kinds of piracy."
So far 5.6 million Chinese copies of the Harry Potter series are already in print, but the publishing house is looking into reprinting the previous four books.
Although Harry Potter is the biggest selling Western book in China, it has not been outselling traditional Chinese children's books.