Cutting and sealing methods of quartz and borosilicate capillary glass-tube using CO2 laser have been investigated. Conventional cutting and sealing glass tube have been done independently from each other. In this study, cutting and sealing processes of glass tube with 1.4 mm outer diameter and 0.25 mm thickness are done simultaneously. Key parameters of laser glass-tube cutting and sealing are laser power, laser spot-size, exposure time and rotation speed of glass tube. Also, the gas pressure-difference between the inside and the outside of glass tube plays a pivotal role in determination of cutting quality. Laser power required for sealing of quartz tube is about 3 times higher than that of borosilicate tube. However, the cutting power of borosilicate tube is slightly higher than that of quartz tube. A clean cut requires 2 or 3 times of rotation within 0.7 sec exposure-time. A proper spot-size of laser should be irradiated on the surface of glass tube, to obtain an enough melting volume for sealing. Differences of cutting and sealing quality beween quartz and borosilicate tubes have been presented in this article.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.