The veteran was 203 not out when captain Darren Sammy declared at tea with his side on 527 for four in Dhaka, with Denesh Ramdin (126no) having become the third centurion of the innings. Opener Kieran Powell made 117 on Tuesday.
Bangladesh responded with 164 for three by stumps, Tamim Iqbal leading the way with a free-wheeling 72.
The Bangladeshi bowlers kept things tight in the morning session but produced few chances, though Chanderpaul was perhaps fortunate to see an early edge drop short of the slips while Ramdin had to be quick on his feet to beat a direct hit.
Ramdin resumed after lunch on 84 and tiptoed into the 90s with a succession of singles. He moved to 98 by edging Shakib Al Hasan for four and reached three figures three balls later, having faced 208 in total.
Attention then shifted to Chanderpaul, needing 25 for his double-century, and a four off Rubel Hossain took him past 190 before his 200 arrived with a cut for two off debutant Sohag Gazi. Three singles saw him match his previous top score, compiled against South Africa in 2005, and his 372-ball innings contained 22 fours. Ramdin hit 11 fours and a six in 236 balls as the pair put on 296.
Bangladesh lost Junaid Siddique for seven when he edged a nasty throat ball from Ravi Rampaul to slip but Tamim responded by hammering four boundaries off the next over, from Tino Best.
New man Shahriar Nafees joined in the fun by twice dispatching Rampaul to the fence. Three boundaries came from Sammy's first over and two more off Rampaul brought up a blistering 50 partnership in 36 balls. But after taking yet another boundary off Rampaul, exuberance got the better of Nafees and he fenced a short ball to keeper Ramdin to depart for 31 from 27 balls.
Tamim, undeterred, charged Sunil Narine and lofted a six to reach a 38-ball half-century, also featuring eight fours, before clearing the rope again two balls later to bring up the Tigers' hundred. He hit two more boundaries off Rampaul but was then becalmed and frustration got the better of him as he toe-ended Sammy to Narine at mid-on.
Naeem Islam (27no) and Shakib (16no) calmed things down thereafter, adding an unbroken 45 in 13 overs by the close.