A stabilized zirconia-based sensor attached with an oxide sensing-electrode (SE) was developed for the selective detection of propylene (C₃H₆), representative hydrocarbon (HC), at high temperature. Among six kinds of commercial oxides examined, NiO-SE gave the highest sensitivity to C₃H₆ at 600°C under the wet condition. However, other sensing characteristics, such as the C₃H₆ selectivity, the response and recovery times, of this sensor were not satisfactory. Thus, to improve the C₃H₆ sensing characteristics, NiO-SE was successively mixed with different oxides. For better reproducibility of response, all the single- or mixed-oxide SEs were prepared by ball-milling. As a result, the sensor attached with NiTiO₃-SE (the initial mixture of 50 mol% NiO and 50 mol% TiO₂) exhibited highly selective and sensitive response to C₃H₆ at 650°C, accompanying with relatively quick response and recovery. In addition, by the comparison of sensing performances of NiTiO₃-SEs fabricated by the different methods, the ball-milling method was found to be the most appropriate from the viewpoint of obtaining high selectivity and sensitivity to C₃H₆.