Infections with herpesvirus have contributed to respiratory, enteric, and neurological disease reports in avian species worldwide. Herpesviruses have been detected in penguin species before but have not been studied extensively. To better understand the impact of these viruses in free-living populations, an initial retrospective survey was performed on a wild population of Humboldt penguins (Spheniscus humboldti) in the Punta San Juan Marine Protected Area, Peru (15°22'S, 75°12'W) using tracheal swabs collected from 28 penguins in 2016 and 34 penguins in 2018. DNA extracted from these swabs was analyzed using a consensus herpesviral PCR assay targeting the DNA polymerase gene, and positive samples were sequenced. A single sample from 2016 was positive for spheniscid alpha-herpesvirus-1 (SpAHV-1), establishing an overall sample prevalence of 1.6% (95% CI: 0-8.6%). The positive animal was an adult male that did not show any clinical signs of herpesviral infection and was otherwise healthy based on physical exam and laboratory findings. This is the first detection of a herpesvirus in penguins at Punta San Juan, Peru, and the first step toward characterizing the implications of SpAHV-1 for Humboldt penguins. This investigation highlights the importance of continual disease surveillance in wild populations over time to monitor for changes that may impact long-term population viability.