Among the other imperial succession theories, the theory of lineal descendent hereditary imperial succession law theory, in which the throne is exclusively ascended to the son born from the legal wife, that of the throne abdication law, which establishes the succession of the throne by abdication, and the crown prince theory, in which the succession is undertaken by pointing the crown prince, can be found.
皇位継承とする説としては他に、特に正妻から生まれた子に伝えるという嫡系皇位継承法説、譲位によって皇位を伝えるという譲位法説、皇太子を立てて継承させるという皇太子制説がある。