We demonstrate a polarization-mediated tunable nanoscale charge transport in Al-doped ZnO (AZO) thin film using conductive atomic force microscopy. In fact, we show that charge transport across an AZO film can be tuned by applying an external nano-Newton force, which confirms the presence of polarization in the film. In addition, we also demonstrate the role of polarization on the inhomogeneous work function using Kelvin probe force microscopy. The observed experimental result is attributed to defect-induced polarization in AZO film and will be a step forward to fabricate mechanical force tunable diode. (C) 2016 Elsevier B.V. All rights reserved.