Lanier County is a county located in the U.S. state of Georgia. It is part of the Valdosta, Georgia Metropolitan Statistical Area. As of 2000, the population is 7,241. The 2005 Census Estimate shows a population of 7,553. The county seat is Lakeland, Georgia. Part of Grand Bay, a 13,000 acre swamp is located in Lanier County.

As of the census of 2000, there were 7,241 people, 2,593 households, and 1,931 families residing in the county. The population density was 15/km² (39/mi²). There were 3,011 housing units at an average density of 6/km² (16/mi²). The racial makeup of the county was 71.61% White, 25.63% Black or African American, 0.57% Native American, 0.36% Asian, 0.04% Pacific Islander, 0.59% from other races, and 1.20% from two or more races. 1.74% of the population were Hispanic or Latino of any race. There were 2,593 households out of which 37.60% had children under the age of 18 living with them, 55.00% were married couples living together, 13.70% had a female householder with no husband present, and 25.50% were non-families. 21.80% of all households were made up of individuals and 9.40% had someone living alone who was 65 years of age or older. The average household size was 2.69 and the average family size was 3.12.