To date the most 3-point field goals made in an NBA game by one player is 12, which has been done by two players. This is one NBA record I expect to be broken in the not too distant future.
This season on November 27, 2010 Dorell Wright of the Golden State Warriors sank 9 out of 12 three point shots to get within shouting distance of the record. Last season J.R. Smith(notes) of the Denver Nuggets made 10 three-pointers in a game and Rodrique Beaubois of the Dallas Mavericks and Chauncy Billups also on the Nuggets both made 9 three-pointers in a game. Two seasons ago Smith made 11 three-pointers in a game.
In addition two more active players Peja Stojakovic(notes) and Ray Allen(notes) have both made 10 three-pointers in a game. And 7 other active players have made 9 three-pointers in a game including Kobe Bryant(notes) who has done it three times and Ben Gordon(notes) and Mike Miller(notes) who have both done it twice. Ray Allen has also made 9 three-pointers in a game twice in the playoffs.