Cooperatives as a form of business entities need capital to run its business. This paper discussed about the issues and the legal aspect of capital, which was related in the act of cooperation No. 25/1992. The results of this study showed that the unclear about rules on reserve funds and the ineffectiveness of rules on bond. In addition there were problem related to the usage of the term "saving", the distribution of reserve funds, the existence of grants and the lack of private sector role in order to promote the cooperatives effort. So, I recommended that the act of cooperatives should regulate clearly about the reserve fund. Also the abolishing rules regarding grants because it was in conflict with the principle of self reliance in cooperative. Beside that, the involvement of private sector was highly needed to optimize the cooperatives through loans and equity capital.