Abstract The non-feeding developmentally arrested infective juveniles (IJs) of entomopathogenic nematodes in family of Steinernematidae and Heterorhabditidae seek out a susceptible insect host and initiate infections. The aim of the research was to examine the continual forming and contribution of IJs produced via endotokia matricida (IJs-EM) of Heterorhabditis bacteriophora Steinernematidae glaseri and S. carpocapsae. The research was conducted at the Laboratory of Nametology of the Saga University Japan (April 2001-April 2002) and the Laboratory of Nematology of the Indonesian Legune and Tuber Crops Research Institute (June 2003-October 2004). The nematode progenies were investigated using greater wax moth Galleria mellonella pre-inoculated with 50 IJs at 25 deg C. Results showed that three reproductive adult generatian were observed at day 18th. There were 135 000 128 000 and 133 000 IJs per insect cadaver produced in H. bacteriophora S. glaseri and S. carpocapsae respectively. Endotokia matricida contributed a higher number of IJs than that of normal mode of IJs production. The rations are 81% 28% and 64% for H. bacteriophora s. glaseri and s. carpocapsae of the IJs total production respectively. Among the generations the highest contribution of IJs was come from the third adult generation bearing endotokia matricida i.e. 63% 24% and 51% for the three nemotode species. Although the IJs-EM ware more transparent compared to normal IJs they were morphologicaly similiar. The results show that endotokia matricida has pivotal role in a species maintenance and survival strategy of entomopathogenic nematodes in extreme enviromental conditions.