Garden Valley is an unincorporated census-designated place in Boise County, Idaho, United States. As of the 2020 census, its population was 377, a decrease of the 394 count on the 2010 census. The mountain setting and recreation opportunities attract visitors from the Boise area. Life there during the pioneer days was quite harsh and economic opportunity was based on logging, mining, and ranching. In later years there was work as hunting guides.