"Large corporates as well as small investors representing a cross section of the society have subscribed for these debentures," the bank said in a statement.
"The highest appetite of investors has been for the fixed interest rate option."
The money will go to boost the bank's Tier II capital and will be used for loans into agriculture, tourism, infrastructure, manufacturing and small and medium enterprises.
Bank of Ceylon is Sri Lanka's largest commercial bank by assets. The state and state entities are its biggest borrowers..