On June 28, 2006, he was selected by the Houston Rockets in the NBA Draft with the 32nd overall pick (2nd pick in 2nd round). Novak ended his rookie season (2006–07) with averages of 1.5 points and 0.7 rebounds in 5.5 minutes per game. He was not active on the Houston Rockets' playoff roster.
During the 2007–08 season, Novak was assigned to the Rio Grande Valley Vipers, a NBA Development League team.[12] On December 16, 2007, the Rockets recalled him from the Development League, where he had spent a month.[13]
In 2008, the Rockets traded him to the Los Angeles Clippers for the option to exchange second-round picks in the 2011 NBA Draft. On February 13, 2008, Novak scored a game winning 3-pointer vs. the Sacramento Kings to win the game 89–87 with 2.5 seconds left, keeping the Rockets' historic 22-game winning streak alive. It was his only basket of the game.[14] On March 15, 2009, Novak hit a 3-pointer at the buzzer to beat the New Jersey Nets, 107–105.[15]
On September 22, 2010, Novak signed a free agent deal with the Dallas Mavericks.[16] On January 5, 2011, he was released by the team.[17] On February 4, 2011, Novak was acquired by the Reno Bighorns of the NBA Development League, but only three days later he was called up by the San Antonio Spurs on a 10-day contract. On March 4, 2011, the Spurs signed Novak for the rest of the season.[18]
After his release by the Spurs on December 19, 2011, Novak signed with the New York Knicks for the veteran's minimum of $1.4 million on December 21.[19] At the end of the 2011-12 NBA season, Novak led the league in 3-point percentage at 47.2%[20] and tied Kevin Durant for third in total 3-point shots made (133).[21] He became an unrestricted free agent at the end of the season. On July 9, 2012, Novak agreed to re-sign with New York for a four-year deal worth $15 million.[22] While playing with New York, Steve Novak accrued a large fanbase. Walt Frazier nicknamed him "Novakaine" after the drug Novocain.[23]
On July 10, 2013, Novak, Marcus Camby, Quentin Richardson, a future first round draft pick, and two future second round draft picks were traded from the Knicks to the Toronto Raptors in exchange for Andrea Bargnani.[24]