洛文县（Loving County, Texas）是美国德克萨斯州西部的一个县，北部、西北部与新墨西哥州相邻，西界佩科斯河。根据美国人口调查局2005年数字显示，人口仅有62人，是美国人口最少的县。2004年人口更只有51人。该县人口近年大幅下降：2000年人口比1990年减少35%，在2000年至2004年之间，人口再下降22%。首治门同是唯一的居民点。最近的较大城市为佩科斯（37公里，人口9501）和新墨西哥州的喀斯巴德（118公里，人口27,463）。奥德萨距离门同120公里（人口90,943，上述皆为2000年数字）。

Loving County is a county in the U.S. state of Texas. As of the 2010 census, the population was 82, making it the least populous county in the United States. Owing partly to its small and dispersed population, it also has the highest median per capita and household income of any county in Texas. Loving County has no incorporated communities; its county seat and only community is Mentone. The county was originally created in 1887, although after being disorganized, it was finally reorganized in 1931.