The cardinals gathered this week to prepare for an October synod that will focus on the family, the Italian news agency ANSA reported.
Francis, the spiritual leaders of the world's Roman Catholics, warned the family is "looked down upon and mistreated" in today's society.
"We are called to acknowledge how beautiful, true and good it is to start a family, to be a family today; and how indispensable the family is for the life of the world and for the future of humanity," the pontiff said.
Cardinals also discussed issues surrounding Catholic faithful who divorce and remarry, but no decisions were made, Vatican Radio reported.
In advance of the October gathering, the Vatican has sent a 38-question survey to national conferences of bishops around the world asking for input on a number of controversial issues, including same-sex marriage and surrogate motherhood.
It will be only the third meeting of the synod since it was created in 1965.
The conclave also issued a statement condemning "every violence in the name of religious membership" around the world, particularly in Africa, adding the church would "work for peace and reconciliation via inter-religious dialogue and multiple works of charity."
The meeting will conclude Saturday with the creation of 19 new cardinals during a special ceremony at St. Peter's Square.