The present work investigates the use of a high-entropy oxygen carriers for chemical looping. The materials are prepared by direct mixing followed by calcination and milling, using at least five metal oxides in equimolar proportions, followed by calcination at different temperatures and times in air. XRD characterization provides strong evidence that the synthesized oxygen carriers possess the hallmark properties of high-entropy oxides, and SEM-EDX analysis shows an overall homogeneous metal distribution. One of the key objectives of this study is to reduce the chemical stress during redox cycles due to the change between reduced and oxidizing phases during CL operation. Oxygen transfer capability is investigated by means of thermogravimetric analysis and batch fluidized bed reactor experiments using different fuels and atmospheres. The oxygen transport capacities for chemical looping (lattice oxygen) and oxygen uncoupling have also been determined. Developed material showed acceptable oxygen transport capacities for lattice oxygen and gaseous oxygen release and sufficient reactivities with syngas and for oxygen release by CLOU. This work opens up a new dimension for the future preparation of oxygen carriers for chemical looping processes, since the vast compositional space of high-entropy oxides provides opportunities to tune both chemical and physical properties.