The utility model relates to a bicycle field especially relates to a grafting structure of bicycle, include: outer pipe support and insert outer pipe support's interior intubate, outer pipe support opening one end rigid coupling has locking mechanism, and outer pipe support lateral wall is opened there is the locating hole, the intraductal positioning mechanism that is equipped with of interpolation, the utility model discloses novel structure, using conveniently, having after the installation through the reference column screens, locking mechanism can realize the firm connection between eachsubassembly of bicycle, and it is convenient to dismantle simultaneously, can reduce substantially the occupation of land space of bicycle after the dismantlement, conveniently stores and carries, canon -call maintenance or replacement when the damage appears in the bicycle subassembly.