The Official Export Credit facility in Thailand has been provided from The Bank of Thailand through the Export-Import Bank of Thailand (EXIM Bank) as one type of financial supports to exporters. However, the credit allocation is done by commercial banks which tend to be more risk averse and, therefore, are likely to finance less to small and medium-size enterprises, that are the main target of this facility. This paper propose an idea of allocating limited credits in order to obtain maximum exports with respect to the potential to export of each industries group by applying a multiple regression model with credit proportions as explanatory variables. Finally, the method of comparative advantage is introduced in order to eliminate the bias caused by scale problems in the original method. Through the allocation scheme presented here, total estimated exports may increase approximately by one-forth.