CHINESE officials and economists are enthusiastic about the idea of issuing state treasury bonds convertible into shares in state-owned enterprises. The Government's bond issue worth 30 billion yuan (about HK$40.5 billion at the official rate) this financial year closed yesterday amid fears that the target would not be met. The Ministry of Finance is expected to announce the result of the sale today. Chinese officials and academics yesterday noted with interest the French Government's ''extraordinary success'' in the sale of bonds. According to a New China News Agency report, an issue worth 110 billion francs (about HK$145 billion) was oversubscribed. The bonds can be converted into stocks this autumn, when the Government sells 21 state-owned firms. The Chinese Government also plans to sell stakes of about 20 or 30 per cent in large and medium-sized state firms and to change them into shareholding companies to cut losses. Officials at the Ministry of Finance, which is in charge of national debt, said that although the Government could not use convertible bonds to stimulate sales at present, the arrangement deserved further study. Professor Cao Fengqi, deputy director of the department of economics and management at Beijing University, also said that issuing convertible bonds was feasible in China. ''The issuance of convertible bonds is certainly the direction of future development in financing the national debt, although there are some technical problems to be resolved,'' he said. Professor Cao said the issue of convertible treasury bonds could make debt issue more marketable because the public was enthusiastic about investing in the stock market. He said that following the riots over stock sales in Shenzhen last year, there had been suggestions that the purchase of stocks could be linked with subscriptions to state treasury bonds. But it was necessary to convert state-owned enterprises into shareholding companies before adopting the convertible bonds method, he said. The next step would be for state-held shares in the enterprises to be traded on the market. This year's sale of treasury bonds was originally to end on May 1, but the issuing period was extended to July 15 because the offer was shunned by state-owned financial institutions and the public. Even lifting the annual interest rate for the bonds in May failed to stimulate public interest in them. Government officials blamed the poor sales on the fund-raising activities of enterprises, including issues of stocks and bonds with much higher interest rates. The State Council had to resort to coercion to ensure the sale of the bonds, including threatening to ban localities which failed to meet their designated quota from listing their stocks.