This paper reports 2D ZnO nanosheets (n)-graphene (p) hybrid architecture composed of dense 2D ZnO nanosheets grown on graphene nanoflakes onto a flexible pencil eraser substrate and its demonstration as a nanodiode rectifier. Graphene (Gr) nanoflakes were deposited by a novel rolling pin method over pencil eraser substrate followed by hydrothermal growth of 2D ZnO nanosheets over Gr. A simple masking procedure was followed using aluminium foil and polyimide tape for selective growth of 2D ZnO nanosheets which can be scalable to large area deposition. XRD analysis confirmed the formation of highly crystalline ZnO and FESEM studies revealed the formation of 2D ZnO nanosheets The as fabricated device displays strong non-linear I-V characteristic similar to that of conventional silicon p-n junction diode. Ideality factor and barrier height were calculated to be 4.8 and 0.380 eV respectively. The device was applied as a half wave rectifier displaying excellent rectifying behavior. Successful fabrication of flexible nanodiode is a step ahead in developing versatile electronic components for analog nanoelectronics that find applications in numerous fields. © 2016 IEEE.