The heavy restrictions will be in place from 6 am on Thursday to midnight on Jul 7, according to a notice from the Cabinet Division on Wednesday.
No one will be allowed to leave home except in case of an emergency during this seven-day period, the notice said. However, people will be allowed to go outside in order to buy medicine or other essentials, seek medical care and arrange burials.
The government had previously vowed strict disciplinary action against those who broke restrictions during the lockdown.
Factories will be allowed to remain open if they follow health protocols, but a decision is still pending regarding courts and banking services, the Cabinet Division said.
All government, semi-public and private offices are to be shut during the duration of the lockdown. Regular road, rail and water travel service is suspended.
The government also ordered the shutdown of all malls, tourist sites, resorts and community centres, and banned large social gatherings such as wedding ceremonies, birthdays, picnics, parties, and political and religious events.
The government enforced a nationwide lockdown in early April after the second wave of COVID-19 began in Bangladesh.
Most restrictions were lifted when the situation improved slightly, but another surge in COVID-19 cases prompted the authorities to put curbs in parts of the country amid the spread of the highly contagious Delta variant, which was first detected in India and has caused a deadly second wave in that country.
Bangladesh registered 7,666 new cases of COVID-19 on Tuesday, bringing the total caseload from the disease to 904,436.
Another 112 people died from the coronavirus in the same period, taking the total death toll from the disease to 14,388, according to the latest government figures.