Diane B. Allen (born March 8, 1948 in Newark, New Jersey) is an American Republican Party legislator, who has been serving in the New Jersey State Senate since 1998, where she represents the 7th Legislative District. She served as the Deputy Republican Conference Leader from 2002 to 2003 and as the Majority Whip from 1998 to 2001. She has been the Deputy Minority Leader in the N.J. Senate since 2004.