Babies with floating thumbs should be treated as early as possible to avoid leaving a memory with deformed features, as some introverted children may develop low self-esteem as a result. The initial treatment plan for floating thumb was thumb thumbing, where the thumb was directly removed and then the index finger was moved to the thumb position to be used as a thumb, after surgery the child had thumb function but only four fingers forever, which some parents found too cruel and unacceptable. Now we are starting from the preservation of five fingers, using the hemimacral bone grafting and reconstruction technique to correct, taking part of the bone from the second metacarpal of the affected hand to rebuild the first metacarpal, the surgery is only performed on the hand, not affecting other parts of the child’s body. The surgery is divided into two stages, the first stage is to move the bone, the second stage is to establish the function, the shape and function is established step by step, after the two stages of surgery, the child can carry out functional exercises, slowly try to do some palmar movements, hold small cotton swabs, small beans, or play some building block games, etc. After a period of exercise, the child will be able to write, hold chopsticks, tie shoelaces, etc., there will be a great improvement compared to the pre-operative.