Chemical composition is one of the most important aspects in the study of Chinese ancient glasses, as it could provide scientific proofs for the technical origin and development of Chinese ancient glasses. It is very necessary to find out some new an alyzing techniques. One of the most remarkable advantages for portable X-ray fluorescence technique is its portability, which allows antiques that can't be allowed to move out of museum to be analyzed. The basic principles, performances and analysis process of the equipment that was improved by OURSTEX company and Center of Sci-tech Archaeology of Shanghai Institute of Optics and Fine Mechanics are presented in detail. Some examples for the application of portable X-ray fluorescence spectrometer in chemical composition analysis of Chinese ancient glass samples excavated from Xinjiang province are also given. The results are compared with that determined by the proton induced X-ray fluorescence technique. There is a potential application for portable X-ray fluorescence technique in on site analysis.