How many Harry Potter's novels are written?

There have been 7 novels.

Harry Potter and the Philosopher's (Sorcerer's) Stone (June 1997 - UK, September 1998 - US)

Harry Potter and the Chamber of Secrets (July 1998 - UK, June 1999 - US)

Harry Potter and the Prisoner of Azkaban (July 1999 - UK, September 1999 - US)

Harry Potter and the Goblet of Fire (July 2000)

Harry Potter and the Order of the Phoenix (June 2003)

Harry Potter and the Half-Blood Prince (July 2005)

Harry Potter and the Deathly Hallows (July 2007)