X-ray and magnetic studies have been made on the intermetallic compound Co_Ti_. X-ray study indicates that Co_Ti_ with the Cu_3Au-type structure has the phase field ranging from about 20.5 to 25.0 at. % Ti (x=0.180~0) below 1,000℃. According to magnetic measurements, Co_3Ti (x=0) is a paramagnetic substance with a practically temperature independent magnetic susceptibility, whereas Co_Ti_ (x>0) is ferromagnetic with Curie points lower than 80°K and saturation magnetizations less than 20.8emu/g