Generally, the two tested neonicotinoides, acetamiprid and thiamethoxam were more toxic against both adults and one day o1d eggs of T. cucurbitacecirum using spraying method than dipping technique method under laboratory conditions. Moreover, positive relationship was established between the number of treated prey (devoured females of T. ctictirbitncearum) consumed per predatory mite, Phytoseitilus macropilis (Banks) (15.28±0.34, 11.17±0.89 and 28.22±0.70) and number of deposited eggs per predator (3.00 ±0.27, 2.33±0.35 and 6.33±0.06 eggs) for acetamiprid, thiamethoxam and control, respectively. Field experiments were carried out with the two neonicotinoides against moving stages of T. cucurbitacearum during 2014 season at Zagazig district, Egypt. Data revealed that slight reduction in T. cticurbitaceariim numbers comparing to control were obtained and recorded 8.29±0.582 and 2.58±0.43 5% in the initial effect of acetamiprid and thiamethoxam, respectively, followed by highly sudden increase in T. cucurbitncenrum numbers reaching to -17.54±1.102 and -62.40±l.434%, in the general effect, respectively. fixed elevation trend was observed in the activities of ᾳ, ẞ and acetylcholine esterase enzymes against field strain of T. cticurbitacearum. Acetamiprid gave the highest significant increase reaching to (85.06, 36.96 and 71.10 % relative to control); while thiamethoxam expressed (51.07, 30.66 and 4.13 % compared to control), respectively.