In this work, we have investigated the etching characteristics of TiO₂ and selectivity of TiO₂ over SiO₂ thin films as resistance in ReRAM using the inductively coupled plasma. The etch rate and selectivity were measured by varying the BCl3 addition into Ar plasma. The maximum etchrate was obtained at 110.1nm/min at BCl3/Ar=5sccm/10sccm, 500W for RFpower, -100v for DC-bias voltage, and 2Pa for the process pressure. The etched TiO₂ surface was investigated with X-ray photo electron spectroscopy. We explained the etching mechanism in two etch mechanisms, physiclas puttering and chemical reaction.