The fire came within 30 yards of the building. It did not touch the structure, but it burned the surrounding landscape.
The flames chewed through olive trees, presidential banners and an internet and cable box that took down the library's network.
The library had to shut down for two days but has since reopened.
The library is home to more than 60 million documents and more than one million photographs covering Reagan's life and administration.
The Easy Fire burned more than 1,800 acres in Ventura County.