Smithville is a city in Lee County, Georgia, United States.

U.S. Route 19 runs through the west side of the city, leading south 12 miles (19 km) to Leesburg, the Lee county seat, and north 13 miles (21 km) to Americus.

Georgia State Route 118 passes through the center of Smithville, leading east 12 miles (19 km) to Leslie and southwest 14 miles (23 km) to Dawson.

According to the United States Census Bureau, the city has a total area of 2.5 square miles (6.5 km2), all of it recorded as land.

As of the 2020 United States census, there were 593 people, 239 households, and 143 families residing in the city.