The previously unannounced Mass is part of the Pope's itinerary for his Philadelphia visit announced by the Vatican June 30.
The announcement also included news of the Pope's planned visit with prison inmates of Curran-Fromhold Correctional Facility in northeast Philadelphia.
Archbishop Charles J. Chaput greeted news of the papal schedule "with great joy and I'm certain that countless individuals in our city, our commonwealth, and our country share that emotion with me."
"As the birthplace of religious freedom, Philadelphia is a city rich in history and diversity. This itinerary recognizes the importance of those qualities and the Pope's desire to witness them firsthand," said Philadelphia's archbishop.
Another stop on the Pope's visit to the city includes an afternoon address Sept. 26 at Independence Hall, birthplace of the Declaration of Independence and the U.S. Constitution. The Pope is expected to speak about religious freedom and immigration, among other possible topics.
The visit with incarcerated men and women at the sprawling 25-acre Curran-Fromhold facility, which houses 8,100 inmates in a complex of prisons, underscores Pope Francis' commitment to extend mercy to the marginalized, including the poor, the sick and, in this case, the imprisoned.
The Pope has declared a Year of Mercy in the Catholic Church to begin Dec. 8. It will emphasize the church's healing ministry to all people "as a field hospital after battle," as the Pope has said.
The morale of the Catholic community in Philadelphia has itself been battered from the past few years of crises including the sexual abuse scandal, financial troubles for the archdiocese and the merger or closing of dozens of parishes and schools.
Msgr. William Lynn, former secretary for clergy of the Philadelphia Archdiocese from 1992 to 2004, is currently serving time at the Curran-Fromhold facility while he appeals a 2012 conviction on a child endangerment charge for his mishandling of clergy sex abuse complaints.
A July 2 Associated Press story said it was not clear if he would still be there when the Pope visits, or if he would be chosen to be in the group of prisoners who will meet the pontiff, but AP said Msgr. Lynn's lawyer said his client would welcome the opportunity.
The visit of Pope Francis to the city and especially his celebration of a Mass in the archdiocese's mother church, the cathedral, "is one of faith and charity, and his words and his presence will be a source of encouragement," said Auxiliary Bishop John J. McIntyre during an interview June 30 at the cathedral.
The iconic brownstone cathedral dating to 1864 only has a capacity of less than 1,500 for the Mass, plus seating for another 500 utilizing video monitors in an adjoining chapel.
Bishop McIntyre said all priests in the archdiocese will be invited to concelebrate the Mass and deacons will be invited as well. As of 2014, the archdiocesan Catholic Directory indicated there are 524 diocesan priests and 288 permanent deacons, plus 293 religious priests, though not all may be able to participate.
He said that because of the great number of men and women religious in the archdiocese as well as laypeople from the archdiocese's 219 parishes, representative groups from each will be selected to attend the Mass, though the process for doing so was not yet available.
"We hope and pray (the Mass) will be a boost to morale, (and) that it will be an instrument of God's gift of faith and hope that we've been given," Bishop McIntyre told CatholicPhilly.com, the archdiocesan news website.
Both the Mass at the cathedral, the prison visit and the address at Independence Hall join other papal events already announced for Philadelphia, including his attendance at an evening Festival of Families cultural celebration Sept. 26 and the public Mass he will celebrate on the Benjamin Franklin Parkway the afternoon of Sept. 27.
That evening there will be a celebration of the World Meeting of Families for supporters and volunteers at Philadelphia International Airport, followed by an official papal departure ceremony there.
"Pope Francis' plans for his visit to Philadelphia seamlessly integrate powerful public moments with more intimate gatherings that are deeply grace filled," Archbishop Chaput said. "It is an itinerary that says, 'I walk with you -- and so does the Lord.' It says, 'Embrace your faith and embrace one another as children of God.' It says, 'God forgives.' And it says 'Come together in celebration.'"
The archbishop called Pope Francis' visit "a true gift for all regardless of faith tradition."
The World Meeting of Families in Philadelphia, being held Sept. 22-25 in advance of the Pope's visit, is expected to draw some 15,000 participants from 150 countries. Pope Francis has called the congress "the central reason for his visit to the United States," Archbishop Chaput said.
The archbishop predicted "the many pilgrims present in September will experience a moment unlike any in the history of our city. The presence of the Holy Father will be electric and charismatic. It has the power to transform all of us in deeply positive ways. It will be our shared responsibility to take that gift and use all that we learn from it to build a better church and a stronger society."