They say it's a 52-year-old man from Santa Fe County and his home will undergo an environmental investigation.
Plague is a bacterial disease of rodents and is generally transmitted to humans through the bites of infected fleas.
It can also be transmitted by direct contact with infected animals including rodents, wildlife and pets.
The first two human plague cases in New Mexico this year were in 15-year-old boy and an 11-year-old girl.
Authorities say both Torrance County residents have recovered.
There was one human plague case in New Mexico last year, two in 2011 and no cases in 2010.
In 2009, there were six cases of the plague and one person died.