The near-field scanning optical microscope, which is integrated with scanning probe microscope technology, has been investigated as a tool for material science, biology, photolithography, and high-density optical recording. In near-field scanning optical microscope, a sub-wavelength sized probe is used to pick up the optical properties of a sample with a resolution limited primarily by the probe size. The configuration of the tip in the application is of utmost importance to the performance of the system. The spatial resolution of near-field scanning optical microscope system is mainly determined by the aperture size of the fiber tip, and the optical transmission properties of the system are highly influenced by the cone angle of the tip as well as the tip surface quality. However, the poor reproducibility in tip fabrication and the low optical throughput are still the major technical difficulties. In this paper, a design of etching automatism for fabricating the tip of near-field scanning optical microscope is proposed. The configuration of the design is very simple and can be actualized easily. The design that considers the main factors that may affect the configuration of fiber tip, makes the experimental condition of fiber tip the same in any condition, and also allows the changes of the experimental condition for fabricating different configuration tips. Static and dynamic etchings and their combinations are studied. The etching process is optimized, and the tips with short tapers, small apertures (about 50 nm) and large aperture cone angles (40 deg.) are successfully obtained. Multiple-tapered tips are also fabricated by using different dynamic regimes. The experimental results show that the design can not only fabricate sharp fiber tips, but also fabricate different configuration fiber tips. The design makes the etching of fiber tips controllable and can satisfy different requirements.