The invention relates to an apparatus and a method for detecting the two-dimensional azimuth and the wavelength of laser. The apparatus comprises a laser device, a grating, a display screen and a camera, wherein the laser device, the grating, the display screen and the camera are sequentially arranged. The apparatus is characterized in that the grating is provided with two groups of mutually perpendicular grating stripes, the two groups of the mutually perpendicular grating stripes are arranged in an adjacent manner, the periods of the two groups of the mutually perpendicular grating stripes are the same, the grating is a metal grating, and the display screen is a transparent display screen. According to the present invention, with the apparatus and the method, the position and the wavelength of the incident light beam can be accurately and simply measured, the measurement stability is high, and the reliability is good; the results can be obtained through the camera real-time capturing measurement and the calculation; the two-dimensional azimuth and the wavelength of the laser can be rapidly obtained; and the apparatus and the method can be used for the alarm technology, and provide the effective reference for the development of the alarm technology.