CSE chief operating officer Renuke Wijayawardhane said three primary dealers in government securities have already become trading members of the stock exchange and a fourth has applied.
There was an existing specialist debt trading member on the exchange.
The exchange said it had taken a series of "aggressive measures to promote a vibrant Corporate Debt Market and provide companies an opportunity to raise debt capital" and giving investors a change to diversify in to fixed income instruments.
The relaxation of rules giving freedom for more dealers to enter the debt market is expected to boost secondary trading in corporate debt.
CSE said it had also simplified requirement for issuing corporate debt and given training to equities brokers about debt instruments.
The CSE said it was in discussions to develop a repo financing mechanism to be made available through the automated trading system to help boost trading.
A REPO or repurchase allows a security to be sold and bought back in a period shorter that its maturity date. It can also be used a financing mechanism to play on the yield curve.