A novel method of preparing polytetrafluoroethylene (PTFE) hollow fiber membrane was presented by utilizing poly (vinyl alcohol) (PVA) can form a gel of two dimensional complex compounds with Boric acid (H3BO3). Effects of H3BO3 on PTFE nascent hollow fiber were investigated, and the results showed that the introduction of H3BO3 effectively reduced the addition of PVA. The configuration named "fibril'' formed between PVA and H3BO3 could be observed in nascent hollow fiber by SEM (Scanning electronic microscopy). Furthermore, Calcium carbonate (CaCO3) particles (60 nm similar to 90 nm) were introduced into PTFE matrix. The interfacial microvoids (IFMs) which were different from the PTFE sintering or node-fibril network structure were obtained. The assumption of the IFMs formation was proposed in this study. Effects of CaCO3 amount and draw ratios on structure and properties of hybrid hollow fiber membranes were analyzed, and the SEM results showed that the IFMs quantity and diameter improved with draw ratio increasing. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 324-330, 2012