Opponents were worried the law will allow discrimination against LGBT people.
Catholic World News reported that the Governor signed it despite threats of loss of business. He said he signed it because he supported the religious freedom of every faith.
He said: "The Constitution of the United States and the Indiana Constitution both provide strong recognition of the freedom of religion but today, many people of faith feel their religious liberty is under attack by government action."
The Indiana Catholic Conference supported the legislation and cited a number of circumstances where it might be applicable, such as adoption agencies, doctors or therapists.