Spectroscopy of the Pakull candidate star for LMC X-1 shows it to be an O7 star with a binary period of approximately 4 days. N III 4640-A emission has approximately antiphased velocities, which implies a mass ratio of 2-3. The secondary has a minimum mass of approximately 2.5 solar mass and a probable mass of 4 solar mass. The secondary is unlikely to be a normal star; if it is the X-ray source, it could be a black hole. A less probable orbit has a 1.34 day period and X-ray source masses greater than 1.9 solar mass.