Sexual behavior, including courtship and mating strategies, remains unexplored for numerous tropical birds. The Andean Lapwing (Vanellus resplendens) is a shorebird inhabiting the High Andes with a poorly known reproductive biology. Here, we aimed to describe behaviors of this species at the beginning of the breeding season. We performed 49 standardized observations of 20 pairs of Andean Lapwings at Laguna de Salinas, Arequipa, Peru, at 4,315 m asl, during the 2021–2022 breeding season. Lapwings in this studied population show (1) social monogamy and evident territoriality, (2) a defined breeding season apparently triggered by rainfall, and (3) a male-biased investment in courtship and territorial defense. Andean Lapwing pairs devoted 15% of their time to courtship activities, males on average doubled the amount of time of females—consisting mostly of nest scraping activities, various displays, and territory defense. Although these observations of Andean Lapwings increase our understanding of breeding strategies in populations inhabiting high-altitude landscapes, the reproductive behavior of most endemic species in the Neotropical mountains remains understudied and requires targeted investigations.