大福克斯县 (Grand Forks County, North Dakota)是美国北达科他州东部的一个县，东邻明尼苏达州。面积3,729平方公里。根据美国2000年人口普查，共有人口66,109人。县治大福克斯 (Grand Forks)。

成立于1872-73年度，县政府组成于1875年3月2日，县名以县治命名 (县治位于雷德湖河与雷德河的交汇之处)。

Grand Forks County is a county located in the U.S. state of North Dakota. As of the 2010 census, its population was 66,861, making it the fourth-most populous county in North Dakota. Its county seat and largest community is Grand Forks. The county was created in 1873 and later organized in 1875.