A ZnO/Zn0.8Mg0.2O double barrier resonant tunneling device (DBRTD) is reported here for the first time. The structure consists of 6 nm ZnO quantum wells and 7 nm Zn0.8Mg0.2O barriers grown by pulsed laser deposition (PLD) on c-cut sapphire substrates. Negative differential resistance (NDR) peaks were obtained at room temperature. The structure is developed by using an indium-tin oxide (ITO) layer both as the back contact electrode and as an etch-stopping layer. The PLD growth quality, wet etching processing for developing the mesa structure, and the I-V characteristics of the device are reported.