This article presents an environmentally friendly, low‐cost polymer nanocomposite, polyvinyl alcohol/sodium alginate‐graphene‐zinc oxide (PVA‐SA/G‐ZnO) based triboelectric nanogenerator by spin coating. ZnO quantum dots of average particle size <10 nm and the graphene oxide (GO)‐doped ZnO are synthesized by co‐precipitation following ageing. ZnO and G‐ZnO particles are filled into the PVA/SA blend system using the solution mixing method. Spin‐coated films of ≈1.2 μm and casted films of 120 μm thicknesses were used to prepare triboelectric nanogenerators (TENGs) to test the output voltage performances. Irrespective of the thickness values, the films gave similar voltage responses with contact electrification. This illustrates triboelectric power generation as a surface charge carrier phenomenon based on morphological analyses by scanning electron microscope (SEM) and atomic force microscopy (AFM). The maximum output voltage of 0.24 V was approximately 5 times higher for the PVA/SA composite containing 2 wt% G‐ZnO nanomaterials compared to the neat polymer are obtained. The nanocomposites also demonstrate excellent dielectric constant (22 times higher) values, suggesting the role of the biodegradable thin‐film TENGs in various self‐powering devices.