The group, called Ordain Women, said it expected several hundred women from around the country to gather outside the LDS Conference Center in hopes that the Mormon church will offer them any unclaimed tickets to the priesthood session.
The group's plans are the latest actions by Mormon women in the past year that seek to address what they say are inequalities between men and women.
Kate Kelly, a 32-year-old member of Ordain Women and a Washington human rights lawyer, said Saturday's demonstration was intended to draw attention to their goal of ultimately "to be ordained to priesthood ... and achieve complete equality - ecclesiastic, clerical, fiscal and otherwise.
Kelly said the event would not be disruptive.
"Our approach has been very respectful, while the idea is revolutionary. In many ways, we will be well-behaved Mormon women," she said.
The semi-annual priesthood session is an opportunity for church leaders to provide instruction to young men about their stewardship and responsibilities associated with the priesthood and to foster a feeling of unity among priesthood holders, said church spokesman Eric Hawkins.
Hawkins said boys in the Mormon church receive priesthood at the age of 12, but acquire increasing responsibilities and duties with age. They aren't ordained or eligible to preside over congregations until they are older and called to do so by church leaders.
Hawkins declined to comment about the decision to deny women tickets to the event, which can attract up to 20,000 men and boys and is sometimes used to announce news or changes in church policy.
"Bolder than ever"
The men's-only priesthood session has been held since the 1940s, according to Hawkins, though the conference in which it occurs goes back a century. In a letter refusing the group's request for tickets for women, the church said women had similar events they could attend.
The request, and the subsequent planned demonstration, has divided church members, who have been openly debating the role of women in the church online for months. The church has 15 million members worldwide, so a change in policy ordaining women would affect millions.
The effort follows several recent actions by Mormon women addressing their role in the church, including a "Wear Pants to Church" last December, using the custom in many congregations for women to attend services wearing dresses as a springboard to raise gender issues.
"The question of women in leadership ... within Mormonism is the most potentially significant, transformative thing since the abolition of polygamy in 1890," said Joanna Brooks, a professor at San Diego State University and the author of "The Book of Mormon Girl: A Memoir of an American Faith."
Brooks is not affiliated with the Ordain Women campaign, which continues to draw controversy.
"Today's Mormon Feminists are bolder than ever, likely due to the support of liberal media outlets willing to exploit, at the drop of a lace hankie, the slightest negative tale to come across their inbox that could potentially convict what they perceive as the male dominant leadership," Kathryn Skaggs, who blogs at "A Well-Behaved Mormon Woman," wrote recently.
But Kelly said Saturday's event was not meant as a protest. She said the group's website has drawn support from Mormon women in France, Brazil, Australia. In the United States, women from Florida to Oregon have contacted her to participate in Saturday's event, she said.
Kelly also said the church's denial included an announcement that the priesthood session would be televised live for the first time, which she considered a "positive step forward."