A method for manufacturing a composition for controlled release including multiple steps is provided. Firstly, an inclusion and a polymer aqueous solution are provided. The polymer aqueous solution has weight percentage ranging from 0.4% to 2%. Then, the inclusion is mixed with the polymer aqueous solution well so as to form a mixture a molding process is performed on the mixture to form a plurality of colloids. Next, a cross-linking process is performed to conduct a reaction between the colloids and an aqueous solution having divalent metal ion so as to form a plurality of reticular structures. Finally, a drying process is performed on the reticular structures. A composition for controlled release is also provided.
