Eight Egyptian isolates of entomopathogenic nematodes (EPN), four belong to the genus Heterorhabditis and four belong to Steinernema were evaluated against adult females of the soft tick Argas persicus and engorged females of the hard tick, Boophilus  annulatus in the laboratory. Results indicated that two EPN isolates (A4 and 10k) of Heterorhabditis were rapidly fatal and have high pathogenicity (100% mortality after 72 hours) against A. persicus when treated with 1000 nematode Infective Juveniles (IJs/ml). Meanwhile, only one isolate (5B) of Steinernema gave accumulated mortality of 93.33% against A. persicus.Furthermore, Heterorhabditis isolates (10 K and A4) caused 93.33% and 86% mortality to B. annulatus. The most effective EPN isolates of Steinernema were 5B and AT4 against B. annulatus, they both gave ca 86.7% mortality. The LC₅₀ values of Heterorhabditis spp. (A4 and 10K isolates) after 72 hrs post infection and LT₅₀ were (27.03 and 257.03 IJs/ml) and (11.94 and 19.2 hrs.), respectively against A. persicus. While, the LC₉₀ was 360.24 and 765.72 IJs/ml for A4 and 10K isolates, respectively. Meanwhile, A4 and 10K isolates exhibited relatively high values of LC_50, LC₉₀ andLT₅₀   against B. annulatus, represented by (358.57±0.71 and 812.83 IJs/ ml ); (1258.9 and 2485.9 IJs/ml.) and (25.64 and 51.28 hrs.), respectively. The present study cleared that Entomopathogenic nematodes (EPN) isolates of the genus Heterorhabditis spp. (A4 and 10K) are potentially useful biological tools for tick control.