The Wellsville Mountains is a mountain range in Box Elder and Cache counties in Utah, United States, that is part of the Wasatch Range.

The range separates the Cache Valley from the Wasatch Front (Bear River Valley), as well as form a portion of the border between Box Elder and Cache counties. Nearly all of the water collected by the Wellsville Mountains drains into the Bear River.

While only moderately tall, they are particularly narrow. For this reason, it is often claimed they are one of the steepest mountain ranges in North America. Box Elder (9,372 feet [2,857 m]) and the Wellsville Cone (9,356 feet [2,852 m]) are its two highest peaks. US-89/US-91 traverses Box Elder Canyon, Dry Canyon, and Wellsville Canyon, beginning east of Brigham City as a four-lane highway, curving north then northeast and entering Cache Valley at Wellsville.

The mountains were named for the nearby City of Wellsville.

• List of mountain ranges of Utah
• Wasatch-Cache National Forest

• Photographs of the Wasatch Mountains