The morphological differentiations between nymphs of Hyalomma anatolicum excavatum, H. dromedarii and H. marginatum marginatum were studied by Scanning Electron Microscopy (SEM) and morphometric analysis. Results showed the morphological characters which aide to identify tick species from each others are chaetotaxy of dorsal and ventral idiosoma, chaetotaxy of Scutum, the position of sternal setae especially front of coxae 11 and 111, the shape and size of spur on coxae Il IV and the shape of spiracular plates and intensity of its pores. H. m. marginatum easy differentiated from other two tick species because it has large size and distinct morphological characters obviously differ from other tick species. Although H. a. excavatum close to H. dromedarii in some characters, it differs easily from H. dromedarii.