The work aims to improve wear resistance of AZ91 magnesium alloy by plating Ti films. Ti films were plated on AZ91 magnesium alloy in the method of DC magnetron sputtering. Adhesive strength of the films was measured on an electronic universal tester in the method of tensile experiment, film-substrate interface morphology was observed with an atomic force microscope (AFM), and film-substrate binding capacity was analyzed provided with different sputtering parameters. Wear resistance of the two samples was analyzed by performing wet friction experiment. Surface morphology of the two worn samples was observed with JsM-670lF cold field emission SEM. Polarization curves of the two samples were measured with polarization curve testing device to determine corrosion resistance. Binding capacity between the Ti films prepared in the method of DC magnetron sputtering and AZ91 magnesium alloy substrate related to sputtering duration. The film-substrate binding capacity was the best when the sputtering duration was 6 min. Allowing for other two parameters, it should take 4 min to prepare the samples in this paper. Wear rate and corrosion current both decrease while corrosion potential increases after AZ91 magnesium alloy is plated with Ti films. Both wear resistance and corrosion resistance are improved by Ti film plating in the method of DC magnetron sputtering.