In this paper, the PVDF/rGO composite films with different mass ratios of reduced graphene oxide (rGO) were prepared by spin-coating method. The layer-by-layer assembly sandwich heterostructure PVDF/rGO (PVDF/rGO-PVDF-PVDF/rGO) piezoelectric nanogenerator (PNG) was manufactured via the layer-by-layer stacking method. The effects of the rGO doping and heterostructre design on the output performance of PNG have been systematically studied. The results showed that the open circuit voltage and short circuit current of the single layer PVDF/rGO composite films PNG were up to 1.76 V and 0.18 μA respectively when the rGO doped mass fraction was 0.4wt%. The open circuit voltage of the PNG with layer-by-layer assembly sandwich-like heterostructure PVDF/rGO0.4-PVDF-PVDF/rGO0.4 was as high as 7.72 V, which was 4.39 times that of the single-layer PVDF/rGO composite PNG, and the short circuit current was as high as 0.69 μA, which was 3.83 times that of single-layer PVDF/rGO composite PNG，which promotes the transfer of electric charge and improves the utilization rate of electric charge. Over 4 000 pressing-releasing cycles tests of the PNG with PVDF/rGO0.4-PVDF-PVDF/rGO0.4 composite layer-by-layer heterostructre have been carried out. The results show that the three-layer heterogeneous structure composite PNG has stable piezoelectric output, which is expected to be widely used in the fields of flexible wearable electronic devices, human-computer interaction and electronic skin.