An amperometric sensor based on yttria-stabilized zirconia (YSZ) and an oxide-based sensing electrode (SE) was examined for the detection of propene. Among the various oxide-based SEs tested, ZnO (+8.5 wt.% Pt) was found to give good sensitivity and selectivity to C3H6 at 600°C. A novel measuring method named “pulsed-potential method” was adopted here to obtain improved sensing characteristics. It was shown that the application of this method to the amperometric sensor resulted in significant enhancement in C3H6 sensitivity. The current response to 400 ppm C3H6 obtained by the “pulsed-potential method” was as high as 95 μA, which is about twenty times higher than that obtained by the conventional “constant-potential method.” It was also found that the C3H6 sensitivity of the sensor was hardly affected by the changes in oxygen and water vapor concentrations in the examined range of 3–20 vol.% and 1–16 vol.%, respectively. Furthermore, the present amperometric sensor exhibited relatively good stability.