Fertilization using slow-release fertilizers to prolong the availability of nutrients for plants and eliminate the diverse effects accompanied by conventional fertilization has become trendy. In this study, slow-release urea fertilizers were prepared through the recrystallization of urea with the addition of raw bentonite and using gelatin as a binder, to make use of the porous and layered structure of bentonite, these materials are inexpensive, biodegradable, and locally available. various slow-release urea fertilizers were prepared with different portions of gelatin and bentonite to study their effect on the release of urea. furthermore, the prepared fertilizers were ground for different periods to study the effect of mechanochemical activation on the pattern of urea release. These raw materials and the prepared fertilizers were characterized by FTIR, SEM, EDX, and XRD which all confirmed the incorporation of urea into the prepared fertilizers. Then they were tested for urea release, which showed that incorporating both bentonite and gelatin expands urea release time. The experiment results were then analyzed for kinetics. The results of this study indicated that the prepared fertilizers are biodegradable, eco-friendly, cost-effective, and can be used as slow-release fertilizers in sustainable agriculture.