Due to be held from October 5 to 19, 2014, the synod, or council, entitled "The Pastoral Challenges of the Family in the Context of Evangelisation" is expected to address among other issues the problem of divorcees remarrying.
The announcement came as the Vatican criticised the German diocese of Freiburg for taking steps to allow divorcees to take communion, which is normally forbidden.
Francis, a more moderate pontiff than his predecessor Benedict XVI, has said he wants more discussion on the Church's relationship with the modern family.