The effect of acetone on R22 (CHCIF2) hydrate equilibrium conditions was investigated. A full view equilibrium cell and associated equipment were designed, fabricated, and used for this purpose. Adding acetone caused an increase in the equilibrium pressure. The investigated mole fractions of acetone in water were 0.02, 0.04, and 0.06. The equilibrium conditions were measured in the pressure range 0.223 to 0.704 MPa. In contrast to methane hydrate in the presence of acetone, the system of R22 + water + acetone showed an inhibition effect for all of the above concentrations of acetone. The existing model for structure II hydrates in the ternary mixtures of methane + water + acetone was applied to the system R22 + water + acetone. The measured dissociation temperatures were compared with the model prediction.