Polyvinyl butyral (PVB) composites were successfully fabricated using graphene as thermal conductivity enhancement filler. The novel composite was prepared via solution blending. Graphene nanoplates (GN) were added to modify thermal conductivity of PVB. Thermal conductivity meter (TCM) and thermo-gravimetric analyzer (TGA) were used to investigate thermal properties of the composites like thermal conductivity and thermal stability respectively. Fourier transformation infrared spectroscope (FT-IR) and X-ray diffractometer (XRD) were used to analyze chemical structure and crystalline phase of the composites respectively. Microstructure of samples was determined by scanning electronic microscope (SEM). The results from the thermal conductivity meter (TCM) showed that the thermal conductivity of sample with a content of 30(Wt%) GN reached 4.521 W/(m K), which was nearly 20.55 times higher than that of pure PVB. The heating and cooling rates of 30(Wt%) GN sample were accelerated noticeably with an enhancement of 28% and 37% respectively, over that of original PVB. The composites have appropriate ionic conductivities as encapsulation materials, which are generally lower than 10(-5) S/m. It is forecasted that the prepared composites have considerable prospects in encapsulation of solar cells and cooling of electronic devices.