The Church in Wales' Governing Body is to consider allowing blessings for same-sex couples who are married or in civil partnerships.
The legislation does not propose allowing gay couples to marry in churches, only to receive a blessing.
"The service is for a blessing only as same-sex couples are unable to marry in church," the Church in Wales said.
The Bill proposes authorising a service of blessing on an experimental basis for five years.
Clergy will be free to decide whether or not they want to use it, the Church in Wales said.
An Explanatory Memoradum says, "Approval of this rite would be stating that the Church in Wales accepts that the loving and faithful commitment of two persons of the same sex, aspiring to life-long fidelity and mutual comfort, and who have made a commitment in civil partnership or marriage, is worthy of acceptance by the Church by asking God's blessing upon their commitment."
The legislation is to be considered at a meeting of the Governing Body being held on September 6.
It is taking place after Governing Body members previously suggested it would be "pastorally unsustainable" for the Church not to offer such a blessing.
A set of pastoral principles has been issued to guide members of the Church in Wales towards "thoughtful and considerate discussions" around what is a controversial topic.
The document states, "There can be no room for seeking to undermine sincerely held views. Neither should we seek to walk away from each other.
"Our union in Christ is at the heart of our life and the bonds and character of our baptism hold us together; sharing a commitment to each other as together we seek the Kingdom of God. We hope these materials will stimulate this quality of engagement."