Kiwifruit (Actinidia chinensis Planch, Hayward cultivar) were ripened at 20°C under a stream of water-vapor saturated air containing 5 ppm ethylene gas. A remarkable rapid softening in the texture and rising of the soluble solids were observed in 24 hr. The total acidity, starch and amylose content decreased during ripening. Both fructose and glucose increased from 2.7% to 5.0% after 5 days of ripening. Sucrose content increased from 0.45% to 2.22% on the second day, then decreased to 1.19% after 5 days. No significant change in chlorophyll and total solids were observed throughout the experiment. There were stepwise decreases in the L and bL values during ripening. The ascorbic acid content decreased from 210 to 190 mg per 100g fresh fruit after 5 days of ripening.