The present study was carried out to evaluate the feasibility of fish scale for the separation of annatto pigment from inert materials. Batch experiments were performed to study the adsorption of the pigment on fish scale adsorbent. The maximum adsorption capacity of the adsorbent for the dye was 12 mg L−1. Three simplified kinetic models viz. pseudo-first-order, pseudo-second-order, and Weber and Morris intra-particle diffusion models were tested to describe the adsorption process. Kinetic parameters, rate constants, equilibrium sorption capacities, and related correlation coefficients for kinetic models were determined. It was found that the present system could be described more favorably by the pseudo-second-order kinetic model. The results of the present study suggest that fish scale can be used beneficially for separation of annatto pigment from inert materials.