Bangladesh, ranked last in the 10-team tournament, turned the form-book upside down when they stunned Sri Lanka by four wickets in the second One-dayer of a three-match home series at Bogra in February this year.
That remains their only triumph in 17 one-day internationals against Sri Lanka.
"We definitely have this (win) in mind and we have to believe that we can beat them again," Bangladesh captain Habibul Bashar told reporters on Friday.
Sri Lanka were without key bowlers Muttiah Muralitharan and Chaminda Vaas in that game, but the Bangladeshi captain said his team were confident of performing well against the full-strength opposition this time.
"They (Sri Lanka) will be stronger this time, but anything can happen in one-dayers. If things go according to our plans, it might be our day tomorrow," said Bashar.
Bangladesh, Sri Lanka, defending champions West Indies and Zimbabwe will play qualifying matches before the main tournament starts on October 15.
Each side will play three league matches before the top two advance to the main draw that features world champions Australia, England, India, South Africa, New Zealand and Pakistan.
Sri Lanka skipper Mahela Jayawardene said his team just could not afford to take any opposition lightly as every match mattered.
"Bangladesh are a good outfit and have been regularly playing international cricket for past five to six years. They have beaten big teams in one-dayers. The defeat at Bogra was also a lesson for us," he said.
Sri Lankan coach Tom Moody said the qualifying matches would help his side adjust to Indian conditions before the real action begins. His team are expected to make it to the main draw on current form.
"We are looking at it (qualifying round) from a positive point of view," said Moody, a former Australian one-day specialist.
"We will play three matches before the main tournament begins and this will help players adjust to the conditions. We are taking it very seriously as every match is important for us."
Moody said his side were different from the one that lost 6-1 in a one-day series in India last year.
"Our team were inexperienced then and young players take time to settle in international cricket. We have been working hard since then and we are now a much better side," he said.
Sri Lanka (from): Mahela Jayawardene (capt), Kumar Sangakkara, Sanath Jayasuriya, Marvan Atapattu, Upul Tharanga, Tillkaratne Dilshan, Chamara Kapugedara, Farveez Maharoof, Chaminda Vaas, Ruchira Perera, Dilhara Fernando, Lasith Malinga, Malinga Bandara, Muttiah Muralitharan.
Bangladesh (from): Habibul Bashar (captain), Shahriar Nafees, Khaled Mashud, Mohammad Rafique, Mohammad Ashraful, Mashrafe Mortaza, Rajin Saleh, Abdur Razzak, Aftab Ahmed, Syed Rasel, Shahadat Hossain, Farhad Reja, Saqibul Hasan, Mehrab Hossain.
Umpires: Steve Bucknor (WIS) and Daryl Harper (AUS), TV umpire: Simon Taufel (AUS)
Match referee: Mike Proctor (RSA)