A puncture-proof structure for tires is provided. The structure forms a spare tire body that can be assembled rapidly and adapted to various tire types by being finely tuned. A tire using the spare tire body is puncture-proof such that when punctured by sharp articles or knifes, the tire can still work to make safe arrival at a nearby repair workshop. This saves a car driver who has a damaged tire from the trouble of shoving the car and from the danger of endangering his/her life, in turn ensuring the public traffic safety.