The 1999 Sybase Open was a men's tennis tournament played on indoor hard courts at the San Jose Arena in San Jose, California in the United States and was part of the ATP World Series of the 1999 ATP Tour. It was the 110th edition of the tournament ran from February 8 through February 14, 1999. Third-seeded Mark Philippoussis won the singles title.

Mark Philippoussis defeated Cecil Mamiit, 6–3, 6–2.

Mark Woodforde / Todd Woodbridge defeated Aleksandar Kitinov / Nenad Zimonjić, 7–5, 6–7^(3–7), 6–4.