To explore the methods of utility assessment using the short form 36.The authors selected 70 people stratified by age, sex, and occupation in a city in Sichuan province, and investigated the preference of the population on each domain or item by paired comparison with other domains or items. Based on the preference, the weights of the domains and items were calculated.The weights of all the 8 domains and the items within 7 domains except the first domain "physical functions" were identified. The total score and the scores of the domains calculated by weighted adding method were significantly different from those calculated by simple adding method. However, only little variation of the scores of the domains between the two methods appeared.Utility calculated by weighted adding method may reflect people's preference to the health states more accurately. However, the value is limited in using weighted adding method for calculating the scores of domains.