Hollow spheres have attracted considerable interest due to their utility in morphology controls of polymer/inorganic hybrid films. Here we report a polyimide/hollow silica (PI/SiO2) hybrid films fabricated by an in-situ sol-gel method. A kind of in-situ micro silica particle with hollow structure in PI/SiO2 hybrid films was discovered by anhydrous sol-gel method and non-catalyst condition. When silica content is 10 wt%, the silica particles are mono-dispersed nano-spheres with an average diameter of 50 nm. At higher silica contents, two morphological silica particles were observed in hybrid films, including hollow silica microspheres and silica nanoparticles. Based on tracking the morphology evolution process, the formation mechanism of this PI/SiO2 hybrid morphology has been proposed. Furthermore, their mechanical properties and thermal stability of these hybrid films are well maintained. This may provide a simpler in-situ method to get polymer/inorganic hybrid films with hollow structure.