It came as Bangladesh kicked off the nationwide COVID-19 vaccination drive.
The DSEX, the main index of the Dhaka Stock Exchange, lost 143 points or 2.5 percent to close at 5,504 points on Sunday.
The move is the biggest since Mar 18, 2020 when the index fell 4.47 percent. The gauge has a similar or greater loss four times in the past year.
The DSEX began to decline within five minutes of the start of trading on the DSE and the downturn continued until the end of the day, with a similar situation transpiring on the Chattogram Stock Exchange.
The share prices of 353 companies and mutual fund units dropped on the Dhaka market, which saw a turnover of Tk 7.71 billion on Sunday.
The capital market has been trending downward for the last two weeks, with DSEX losing a total of 188 points during that time.
Meanwhile, the turnover in the CSE increased by Tk 110 million as Tk 44 million worth of shares and mutual funds were exchanged.
As the mass vaccination campaign began across the country, the shares of Beximco Pharma, the importer of the vaccine in the country, dropped around 8 percent.