Red dragon fruit (Hylocereus polyrhizus) is a widely cultivated variety with a larger fruit size and attractive flesh color. One of the organisms associated with red dragon fruit plants is ants. The general role of ants in plants is insect pests, predators, pollinators, and decomposers. This study aims to determine the types of Formicidae insects and their role as pests on red dragon fruit plants. This study uses descriptive analysis which includes the identification of Formicidae insects, their populations and roles in dragon fruit plants. Formicidae insects associated with red dragon fruit plants consist of 4 genera and 9 species, namely Solenopsis invicta, Acropyga sp., Anoplolepis gracilipes, Iridomyrmex sp., Polyrhachis carbonaria, Eurenolepis sp., Pheidole megachepala, Dorylus sp. and Gesomyrmex sp. Their roles vary from plant pests, predators and pollinators.