List of The New York Times number-one books of 2009

The American daily newspaper The New York Times publishes multiple weekly lists ranking the best selling books in the United States. The lists are split in three genres—fiction, nonfiction and children's books. Both the fiction and nonfiction lists are further split into multiple lists.

Fiction
The following list ranks the number-one best selling fiction books, in the hardcover fiction category.

The most popular books of the year were The Lost Symbol, by Dan Brown and The Associate, by John Grisham with respectively 7 and 4 weeks at the top. The author James Patterson was at the top for four different books (8th Confession, Swimsuit, Alex Cross's Trial and I, Alex Cross).

Nonfiction
The following list ranks the number-one best selling nonfiction books, in the hardcover nonfiction category.