To determine the tick species that bite humans in the province of Soria (Spain) and ascertain the tick-borne pathogens that threaten people's health in that province, 185 tick specimens were collected from 179 patients who sought medical advice at health-care centres. The ticks were identified, and their DNA examined by PCR for pathogens. Most ticks were collected in autumn and spring (59 and 57 respectively). Nine species of ticks were identified, the most frequent being Dermacentor marginatus (55·7%), Ixodes ricinus (12·4%) and Rhipicephalus bursa (11·9%). Ninety-seven females, 66 males, 21 nymphs and one larva were identified. Twenty-six ticks carried DNA from Rickettsia spp. (11 Rickettsia slovaca, 6 Rickettsia spp. RpA4/DnS14, 1 Rickettsia massiliae/Bar29, and 8 unidentified); two ticks carried DNA from Borrelia burgdorferi sensu lato and seven ticks harboured DNA from Anaplasma phagocytophilum.