Polyimide composite movies have been extensively utilized in some superior subject of microelectronic units, precision devices and nationwide protection functions. Graphene quantum dots have nice utility potential in polymer doping modification due to their good mechanical energy, excessive particular floor space and glorious tunability of bodily and chemical properties. On this paper, Graphene quantum dots are ready by pyrolysis at completely different temperatures. The outcomes present that completely different response temperatures have an excellent affect on the scale and dimension distribution of graphene quantum dots. When the pyrolysis temperature is 200 °C, the scale of graphene quantum dots is uniform at 3–5 nm. Graphene quantum dots-polyimide nanocomposite movies ready by in-situ polymerization present glorious mechanical properties. When the doping quantity of graphene quantum dots is 0.5 wt%, the tensile energy and elastic modulus of the composite movies can attain 130.24 MPa and a pair of.93 GPa respectively, that are 41.3% and 108% greater than that of pure polyimide movies, respectively. Furthermore, the thermal stability of polyimide composite movies will increase with the rise of the doping quantity of graphene quantum dots. This exhibits that graphene quantum dots have good dispersion in polyimide matrix and might successfully enhance the interface of composites. These outcomes present a profitable preparation methodology to assist information to manufacture graphene quantum dots-polyimide composite movies with excessive efficiency for the superior functions.