Peridroma saucia (Hubner) (Lepidoptera: Noctuidae) is a polyphagous pest that attacks nearly all vegetable fields in Turkey. Entomopathogenic nematodes (EPNs) are successfully used as a biological control agent. The efficacy of four EPNs, Steinernema carpocapsae, S. feltia, Heterorhabditis bacteriophora and H. indica against the last instar larvae of the pest, was tested under laboratory conditions. Suspensions of nematodes were applied at four concentrations (10, 50, 100 and 200 infective juveniles/larva) at 25 +/- 1 degrees C. Mortality percent was evaluated 48 and 96 h post application. Mortality rate increased with increasing concentrations. The highest effect caused 70% mortality by H. bacteriophora and H. indica species after 48 h exposure time and the lowest mortality was 33% for Steinernema carpocapsae. There was no significant difference between virulence of Heterohabditis spp. and Steinernema spp. when tested against the larvae of P. saucia after 96 h exposure time. These results showed that EPNs have a significant potential in the biological control of P. saucia under controlled conditions.