To provide a building tension holding instrument which positively reinforces and holds a building during jack-up operation to alleviate a load imposed on the building, to provide a building tension holding method which can hoist the building without imposing an excessive load on the building, is superior in safety and workability, dispenses with the removal of residents, furniture, etc., from the building even during the jack-up operation, and can be carried out without limiting narrow locational conditions, and to provide a jacking method which allows short-term work and is superior in cost benefit and convenience.

The building tension holding instrument is comprised of flexible line members 12, pulling members 13, and abutting members 14, 14a. Each line member 12 is formed of one or more of a rope, a wire, a belt, etc., which is wound on the periphery of the building 10. Each pulling member 13 connects one end of the line member 12 to the other end of the same, to thereby adjust the distance between the one end and the other end. The abutting members 14, 14a are arranged on wall portions and column portions at respective corners around the building and abut on the line members 12.