In order to meet the requirements of a designed and manufactured micro-Raman spectrometer with numerical aperture of 0.04 and operation wavelength from 781 nm to 1014 nm, two types of the optical systems of the Raman probe are designed. One is the traditional spherical system, and the other, the aspheric system. The scatter light collection system is a single lens with large numerical aperture, and the light converge system is a kind of telephoto lens formed by a “thick double-cemented lens”. An excellent telephoto ratio of 0.59 of the system is achieved, which reduces the optical system of the probe greatly. It is shown that the traditional spherical system has a numerical aperture of 0.33 at the object space, with the spot diagram radius less than 30 μm and the relative illumination at the image plane higher than 80%. The aspheric system has a numerical aperture of 0.4 at the object space, with the spot diagram radius less than 20 μm and the relative illumination at the image plane higher than 80%. The overall length of the optical system is 150 mm, which meets the requirements of the compact and portable micro-Raman spectrometer.