The rates of carbon dioxide and ethylene production and the levels of 1-aminocyclopropane-1-carboxylic acid (ACC) and polyamines, putrescine and spermidine, in chilling-sensitive water convolvulus and resistant chingensai were measured during storage at constant 5°C and 20°C or with temperature rise from 5°C to 20°C. Water convolvulus stored at constant 5°C or transferred from 5°C to 20°C on day 3 developed chilling injury on day 4, while chingensai showed no chilling injury at any temperature storage. Following temperature rise to 20°C with two periods of storage at 5°C, water convolvulus showed differences between the two in the rates of carbon dioxide and ethylene production and the levels of polyamines, putrescine and spermidine; however, chingensai remained essentially the same. These results suggest that chilling stress affected the ethylene biosynthetic pathway and polyamine metabolism in chilling-sensitive water convolvulus but not in resistant chingensai.