Optical design of the refractive camera for the LAMOST NIR spectrograph prototype. The layout shows a six-lens design incorporating two aspheric elements for effective correction of spherical and comatic aberrations. The last lens also functions as the detector window. The camera has a focal length of 260 mm and operates at F/1.3. Its design covers the mechanical detector envelope (61.22 ×  61.22 mm²), providing ample alignment tolerance to ensure excellent image quality across the scientific field of view.