Mayor Jim Fouts says all religious faiths are invited to Thursday's program. It starts at noon.
Fouts calls it "a unique opportunity for all religious groups to unite and pray for world peace, a healthy economy and guidance in our daily lives."
The city has allowed the distribution of religious materials and discussion of religious beliefs at church-run "prayer stations" in City Hall since 2009.
An atheist man set up an informational booth last month promoting free thought, the use of reason and separation of church and state after winning a lawsuit to have it inside City Hall.