The leaching kinetics of cadmium from scallop waste in dilute sulfuric acid was investigated by examining the effect of temperature (293-333 K), pH (1.5-2.5), and particle size on the leaching rate. The kinetics of the cadmium extraction process with intraparticle diffusion was reasonably interpreted according to the shrinking core model as a rate-determining step in accordance with the value of the activation energy, 15.9 kJ/mol. Increasing temperature, and decreasing pH and particle size positively influence the extraction of cadmium from the uro.