The embodiments of the invention provide a speckle structured light-based high-precision depth calculation method and system. The method includes the following steps that: the image information of acalibration plate on a reference plane is acquired, the coordinates of feature points of the image information in a camera coordinate system are calculated through a camera calibration algorithm; theplane equation of the reference plane in the camera coordinate system is calculated according to the coordinates of the feature points in the camera coordinate system; the speckle pattern of the reference plane is acquired, the parallax of speckles in the pattern is calculated according to the speckle pattern; and the depth of a target position point on the reference plane is calculated accordingto the plane equation in the camera coordinate system and the parallax of the speckles. According to the method provided by the embodiments of the invention, the precise pose of the reference plane iscalculated through the plane equation and the parallax of the speckles, and therefore, error transmission is fundamentally reduced, and depth calculation accuracy is greatly improved.