Puerto de Luna, or gateway of the moon, was possibly named by Coronado when he camped here and seeing the moon rise through a gap to the east. Actually, the Luna family pioneers settled here in the 1860s at the mouth of Puerto Creek.
Puerto de Luna was the county seat of Guadalupe County in the 1880s with 1,500 residents. Later, the county seat moved upstream to Santa Rosa. Post office was in operation from 1873 to 1966.