Objective:To assess the acaricidal activity of titanium dioxide nanoparticles(TiO_2 NPs)synthesized from flower aqueous extract of Calotropis gigantea(C.gigantea)against the larvae of Rhipicephalus(Boophilus)microplus[R.(B.)microplus]and the adult of Haemaphrysalis bispinosa(H.bispinosa).Methods:The lyophilized C.gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO(OH_2)(10 mM)and magnetically stirred for 6 h.Synthesized TiO_2 NPs were characterized by X-ray diffraction(XRD).Fourier transform infrared spectroscopy(FTIR),Scanning electron microscopy(SEM),and Energy dispersive X-ray spectroscopy(EDX).The synthesised TiO_2 NPs were tested against the larvae of R(B.)microplus and adult of H.bispinosa were exposed to filter paper impregnated method.Results:XRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm.The functional groups for synthesized TiO_2NPs were 1405.19,and 1053.45 cm~(-1)for-NH_2 bending,primary amines and amides and 1053.84and 1078.45 cm~(-1)for C-O.SEM micrographs of the synthesized TiO_2 NPs showed the aggregated and spherical in shape.The maximum efficacy was observed in the aqueous flower extract of C.gigantea and synthesized TiO_2 NPs against R.(B.)microplus(LC_(50)=24.63 and 5.43 mg/L and r~2=0.960 and 0.988)and against H.bispinosa(LC_(50)=35.22 and 9.15 mg/L and r~2=0.969 and 0.969).respectively.Conclusions:The synthesized TiO_2 NPs were highly stable and had significant acaricidal activity against the larvae of R.(B.)microplus and adult of H.bispinosa.This study provides the first report of synthesized TiO_2 NPs and possessed excellent anti-parasitic activity. Objective: To assess the acaricidal activity of titanium dioxide nanoparticles (TiO 2 NPs) synthesized from flower aqueous extract of Calotropis gigantea (C. gigantea) against the larvae of Rhipicephalus (Boophilus) microplus [R. (B.) microplus] and the adult of Methods: The lyophilized C. gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO (OH 2) (10 mM) and magnetically stirred for 6 h. Synthetized TiO 2 NPs were characterized by X- ray diffraction (XRD). Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive X- ray spectroscopy (EDX) .The synthesised TiO 2 NPs were tested against the larvae of R (B.) microplus and adult of H. bispinosa were exposed to filter paper impregnated method. Results: XRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm. The functional groups for synthesized TiO 2 NPs were 1405.19, and 1053.45 cm -1 for-NH 2 bending, primary amines and amides and 1053.8 4 and 1078.45 cm -1 for CO.SEM micrographs of the synthesized TiO_2 NPs showed the aggregated and spherical in shape. The maximum efficacy was observed in the aqueous flower extract of C. gigantea and synthesized TiO_2 NPs against R. (B. ) against micropris (LC_ (50) = 24.63 and 5.43 mg / L and r ~ 2 = 0.960 and 0.988) and against H. bispinosa (LC_ (50) = 35.22 and 9.15 mg / L and r ~ 2 = 0.969 and 0.969 respectively). respectively. Conclusions: The synthesized TiO 2 NPs were highly stable and had significant acaricidal activity against the larvae of R. (B.) microplus and adult of H. bispinosa. this study provides the first report of synthesized TiO_2 NPs and possessed excellent anti-parasitic activity.