A species of Neotropical suckermouth armored catfish (family Loricariidae), tentatively identified as the Amazon sailfin catfish Pterygoplichthys pardalis, is a highly invasive, non-native species in Southeast Asia. In Thailand, the spread of P. pardalis is an increasing concern because of the possibility that these non-native catfish are negatively impacting freshwater biological resources. In this study, we conducted a series of laboratory experiments to investigate the food preferences of P. pardalis as well as the interactions of this catfish with the native bighead catfish Clarias macrocephalus (Gunther, 1864). We also conducted laboratory experiments to evaluate the potential use of three different native piscivorous fishes as biological control agents. Laboratory results revealed that P. pardalis in aquaria conditions readily consumed the eggs and fry of Nile tilapia Oreochromis niloticus (Linnaeus, 1758) and that large specimens P. pardalis preferred O. niloticus eggs over Tubifex worms. Pterygoplichthys pardalis at all sizes also more readily fed on nonmoving food items rather than mobile tilapia fry. Our laboratory observations of the interactions between P. pardalis and C. macrocephalus also revealed that the growth rate of C. macrocephalus was not affected by P. pardalis because the native catfish fed at a faster rate. Laboratory experiments indicated that two native fishes, the bagrid catfish Hemibagrus wyckioides (Fang & Chaux, 1949) and the marbled sleeper Oxyeleotris marmorata (Bleeker, 1852), readily prey on and demonstrated potential to control juvenile P. pardalis (0.6–10 cm total length [TL]). Pterygoplichthys pardalis larger than 10 cm TL were not consumed, probably because of their relatively large pectoral and dorsal spines deterred against being swallowed by these predators. The giant pangasius, Pangasius sanitwongsei (Smith, 1931), was less effective as a predator on P. pardalis. Our laboratory experiments indicate that these invasive catfish may have a negative impact on the wild as potential egg predators; however, certain large native predatory fish might be useful control agents.