Abstract: Objective To introduce the index finger pollicization for deformities of the floating thumb in adult patients and observe the recovery of its function after operation. Methods Deformities of the floating thumb in 3 patients underwent index finger pollicization.The patients were followed up for 2 years after operation. Results The operation was successful for 3 patients.The patients were followed up for 2 years after operation.The space between the thumb and the index finger was increased 70°-90°,which was close to that of the normal side.The functions of the opposing metacarpopharlange and finger to finger test were excellent.The resolving feel of the thumb and finger tips was as good as that of the normal side.The appearance of the wounded limb was much better after operation than before operation. Conclusion Index finger pollicization is a safe and reliable procedure for deformities of the floating thumb in adult patients,and can improve the appearance and function of the wounded limb.