Declan Joseph O'Scanlon Jr. (born June 9, 1963) is an American politician who has served in the New Jersey Senate since 2018, representing the 13th Legislative District. A member of the Republican Party, he previously served in the New Jersey General Assembly from 2012 to 2018. Prior to the 2011 redistricting, O'Scanlon represented the 12th Legislative District in the Assembly from 2008 to 2012.