克拉克默斯县（Clackamas County, Oregon）是位于美国俄勒冈州西北部的一个县。面积4,867平方公里。根据美国2000年人口普查，共有人口338,391。县治俄勒冈市 (Oregon City)。

1843年7月5日设区 (是最早的四个分区之一，当时尚未创建准州)，1845年改置县。县名纪念奇努克族的一支、克拉克默斯人。

Clackamas County /ˈklækəmᵻs/ is a county located in the U.S. state of Oregon. As of the 2010 census, the population was 375,992, making it the third-most populous county in Oregon. Its county seat is Oregon City. The county was named after the Native Americans living in the area, the Clackamas Indians, who were part of the Chinookan people.