The 1998 NECBL season was the fifth season of the New England Collegiate Baseball League. The league expanded to seven teams with the addition of the Keene Swamp Bats of Keene, New Hampshire. The Swamp Bats were the league's first New Hampshire franchise.
In the semifinal playoff rounds, Middletown defeated Danbury 2-0, and Torrington defeated Rhode Island 2-0. In the final round, Middletown defeated Torrington 3-1 to win their second consecutive NECBL championship.