Mona is a city in Juab County, Utah, United States. As of the 2010 census it had a population of 1,547. It is part of the Provo–Orem metropolita…Mona is a city in Juab County, Utah, United States. As of the 2010 census it had a population of 1,547. It is part of the Provo–Orem metropolitan area. The city is about halfway between Santaquin and Nephi along Interstate 15. The population was 850 at the 2000 census, which at the time was sufficient under Utah state law for Mona to become a city. It did so in 2001.