The vermiculated sailfin catfish (Pterygoplichthys disjunctivus Weber 1991) is considered one of the most invasive fish species worldwide. Although it has been introduced in various aquatic ecosystems in the Philippines, studies on its invasion impacts and distribution in the country are still limited. In this paper, we present additional information on the occurrence of P. disjunctivus based on our recent fish survey in March 2023. The study was conducted in Naujan Lake National Park (NLNP), Oriental Mindoro, the Philippines, a Ramsar Wetland Site recognized for its international importance. During our survey, a single individual of P. disjunctivus was caught as a bycatch in the gill nets used by local fishermen. The species’ presence poses a significant threat to the lake’s native biodiversity and ecosystem. This finding highlights the urgent need for comprehensive monitoring and management strategies to prevent the proliferation of this invasive species and further unregulated introductions of non-native species to safeguard the ecological balance of NLNP and its native biodiversity.