An optical disk information device includes a laser light source that emits a luminous flux with a wavelength λ, an objective lens having a numerical aperture NA, a splitting element, a photodetector, a central portion amplifier, at least two end portion amplifiers, an adder, a control signal processing section having a tracking switcher that inverts a polarity of a tracking control signal depending on whether a track scanned by a condensing spot corresponds to a land portion or a groove portion, and a gain controller that, when the polarity of the tracking control signal is inverted, switches gains of the central portion amplifier and the end portion amplifiers and sets the gain of the central portion amplifier substantially lower than the gain of at least one of the end portion amplifiers so as to reduce crosstalk from adjacent tracks in the optical disk.