White sword jack bean (koro bean) contains higher protein than the protein contained in tubers. The protein content of koro beanis 27.4%. With a fairly high protein content in koro beanit is possible to be able to process the coagulation of its protein content into a product of korocurd. The coagulation process is the most important step in making curd. Lactone coagulants, such as Glukono Delta Lactone, are widely used in the process of making silken curd with a soft texture. The method used in this research is the Randomized Block Design method. The variables examined in this study were the concentration of GDL 1.0% (w/v), 1.2% (w/v), 1.4% (w/v), 1.6% (w/v), 1 8% (w/v). The results of this study indicate that the GDL concentration of 1.8% (w/v) has a significant influence on the protein level of koro curd.