Standard Effective Temperature (SET) is the best thermal comfort index induced from human heat balance model so far. SET is used to analyze the therma l comfort in nonheating period in Harbin. In actual environment, one person ma y feel too cold or too hot when he/she wears different clothes and takes differen t activity. For lots of people, the environment can't make all of them feel comf ort because every individual has different feeling about the environment and has different standard of comfort. So, discomfort index (DISC) is adopted in this p aper to analyze the degree of discomfort in Harbin. Based on data of hourly temperature, hourly relative humility and hourly wind speed in nonheati ng period (from 20 April to 20 October) in 2005 in Harbin, average threehour te mperature, relative humility and wind speed of every period of ten days from 20 A pril to 30 May and from 1 September to 20 October are calculated. Average three hour temperature, relative humility and wind speed of every month from June to O ctober are calculated too. And based on the thermal comfort figures in the book “Architecture. Climate.Energy", the method of interpolation is applied to obta in the SET and DISC values of everythreehour of every period of ten days. Som e conclusions are: If people in Harbin wear clothes for which clothing thermal res istance is 0.6, such as trousers, semisleeve shirt or longsleeve shirt, from June to August and people wear clothes for which clothing thermal resistance is 0 .9, such as trousers, longsleeve shirt, and jacket in other periods, there are no period to make eighty percent of people feel thermal comfor t when people work at a table in a room. From 10:00 to 18:00 in a day of thelasttenday of May to thefirsttenday of September, seventy per cent of people feel comfort. People can feel cold in 75 percent of a day during the pe riod from thelasttenday of April to thefirsttenday of May. People ca n feel very cold in half a day during the period from thelasttenday of Sep tember to thefirsttenday of October. So, in nonheating period in Harbin, people may wear warmer clothes to offset the discomfort. 