"Complacency is way out of our mind and it is important to set the standards," Lara told reporters on Tuesday.
Defending champions West Indies are now just one win away from qualifying for the main draw after having thrashed Zimbabwe by nine wickets in their opening match at Ahmedabad on Sunday.
Sri Lanka, Bangladesh, Zimbabwe and the West Indies are playing in the qualifying round, with the top two sides making it to the main draw that features Australia, England, India, South Africa, New Zealand and Pakistan.
Bangladesh need to win their remaining two games after losing to Sri Lanka in their opening match at Mohali on Saturday.
Lara said his team needed to put in a good show against Bangladesh to make sure of moving into the second round.
"It's a very important match for us. If we win tomorrow, we qualify. We also have an opportunity to go through the next round with some competitive cricket under our belt," he said.
"They (Bangladesh) are a competitive team. They have beaten Australia (last year) and you don't need to say anything else, and that too in Cardiff and not in Banlgadesh, and that shows they have the ability to play."
The West Indies skipper said all-rounder Chris Gayle's form augured well for the team ahead of main matches.
"Chris has proved he is among the best in the world. He is a match-winner with his bowling, batting and fielding and his influence gives us the lift. He is an important part of the team," said Lara.
Gayle was named man of the match against Zimbabwe, scoring a brisk 41 and taking three wickets with his off-spin.
"Contributions from everyone is more necessary than individual performances. We have players like (Shivnarine) Chanderpaul, Gayle and (Ramnaresh) Sarwan and it is important that everyone contributes," said Lara.
The West Indies were slightly worried over the fitness of Sarwan, Runako Morton and Dwayne Smith, suffering from viral infections.
"Sarwan and Morton are recovering well and no one has been ruled out of tomorrow's game," the West Indies team spokesman said.
Bangladesh coach Dav Whatmore said his team were capable of putting up a better show in the must-win match.
"We took a lot of positives from the previous game," he said.
"The team fought hard as they managed to bat their full quota of 50 overs after reeling at 78-4. It is a good sign. We have talented youngsters to make it a competitive unit. This is the game we have to win."
West Indies (from): Brian Lara (capt), Ramnaresh Sarwan, Chris Gayle, Shivnarine Chanderpaul, Runako Morton, Dwayne Bravo, Dwayne Smith, Carlton Baugh, Corey Collymore, Fidel Edwards, Ian Bradshaw, Jerome Taylor, Marlon Samuels, Wavell Hinds.
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: Billy Bowden (NZL) and Simon Taufel (AUS), TV umpire: Steve Bucknor (WIS)
Match referee: Ranjan Madugalle (SRI)