Chanderpaul remained unbeaten on 123 for his 26th Test century while Powell notched 117 for his second to help the West Indies to an imposing 361-4 at close on the opening day after Darren Sammy won the toss and opted to bat.
The 38-year-old, who joined Powell at the stroke of lunch on 106-3, not only played a calm knock but also guided his young colleague to reverse Bangladesh's early advantage on a slow turning Shere Bangla stadium pitch.
Chanderpaul, ranked fifth in the world, added an invaluable 125 runs for the fourth wicket with Powell before strengthening the West Indian position during an unbroken 130-run partnership with Denesh Ramdin who was 52 not out at close.
Bangladesh had looked good in the first hour when debutant off-spinner Sohag Gazi, opening the attack with the new ball, dismissed Chris Gayle (24) and Darren Bravo (14) before paceman Shahadat Hossain knocked Marlon Samuels for 16.
“We are in a commendable position,” said Powell, whose first century came against New Zealand in July this year. “I enjoyed the innings and it was good to have Shiv at the other end, he guides others well.”