The event will take place Monday from 6 p.m. to 8 p.m. at the Historic Utah County Courthouse.
The demonstration is part of a larger movement, United for Marriage: Light the Way to Justice coalition.
The event will feature speakers, singing and a candlelight vigil.
BYU Student Curtis Penfold said the demonstration may surprise some in the area.
"'There are many BYU students and Utah County citizens that support marriage equality, and people just don't know that," he said. "We want to add our voices to the many around the nation that recognize marriage as a beautiful thing."
Historic Utah County Courthouse
51 South University Avenue
Rally starts at 6 PM, candlelight vigil at approx. 7:40