In this study, we present programming speed enhancement in amorphous oxide semiconductor memory thin-film transistor (TFT). We developed a nonvolatile memory transistor based on InZnSnO back-channel-etch TFT with InGaZnO charge storage layer inserted between gate insulators. We proposed double-gate (DG) and body-contacted (BC) memory structure to improve memory erase speed, which is the most important issue in oxide memory TFTs. DG memory did not show sufficient improvement due to large voltage drop in second gate insulator. BC memory, which can control back-channel potential directly, showed significant improvement on memory program/erase speed.