An optical pickup apparatus is provided for use in a recording/reproducing apparatus to record/reproduce information on/from recording media having different formats. Such an optical pickup apparatus comprises a dual wavelength laser diode; a hologram module arranged to split a light which is incident to a recording medium into a plurality of beams; and a photo-detector arranged to receive a light beam reflected from the recording medium and detect an information signal and a signal for servo control. Each of the split beams is focused on a predetermined position corresponding to a format of the recording medium. The light beams reflected from the recording medium are detected by the photo-detector to generate a focus error signal and a tracking error signal. Thus, the optical pickup apparatus records and reproduces information on and from recording media having different formats by using a hologram of a simple pattern. The optical structure of the optical pickup apparatus is simple which enables easy assembly and manufacture and provides signal regeneration when operating in a high temperature.