Abstract: Disclosed is a visual imaging device based on PS-OCT for early demineralization and caries of dental hard tissues, comprising a laser light source for emitting a laser light, a coupler for receiving and dividing the laser light emitted by the laser light source into a reference laser light and a detection laser light; wherein the reference laser light backtracking to the coupler and the detection laser light backtracking to the coupler are coupled and then passed through a transmission grating and a convex lens to input as an optical signal into a linear CCD detector for converting the optical signal into an electrical signal which is then input to a computer control system and collected by a built-in capture card; and the computer is configured to perform a three-dimensional reconstruction of an image and perform two-dimensional cross-section image analysis; and the computer control system is connected to the scanning galvanometer to control a vibration of the scanning galvanometer.