North, 28, enjoyed a short stint in Bristol at the start of this season and has plenty of other experience in English conditions with Lancashire, Durham and Derbyshire.
"I am extremely proud to return to Gloucestershire for the 2008 season," said North.
"I thoroughly enjoyed my brief stint there earlier this year and am really looking forward to the opportunity of playing a full season."
"Mark Alleyne has assembled a talented and ambitious squad that looks set for a bright future, and I am grateful for the chance to contribute towards the success of the team next year."
Gloucestershire chief Executive Tom Richardson added: "Obviously we are delighted that Marcus has signed for next season at such an early stage.
"He played extremely well during the first part of the season and he significantly strengthens the side."