Lawrence Stephen McMahon (December 26, 1835 – August 21, 1893) was a Canadian-born prelate of the Catholic Church. He served as Bishop of Hartford from 1879 until his death in 1893.
Lawrence McMahon was born in St. John, New Brunswick to Owen and Sarah McMahon, and in 1839 came with his parents to the United States, where they settled in Charlestown, Boston, Massachusetts. His younger brother John later became pastor of St. Mary's, Charlestown Receiving his early education at the public schools of Boston, he entered the College of the Holy Cross in Worcester at age 15, and remained there until the college was destroyed by fire in 1852. He then studied rhetoric at the Collège de Montréal, Quebec, and philosophy at St. Mary's Seminary in Baltimore, Maryland.
Bishop John Bernard Fitzpatrick of Boston had arranged for McMahon to study at the Pontificio Collegio Urbano de Propaganda Fide, but given the political unrest in Italy at that time,