Background : Since 2001 the Korean Association of Health Promotion has attempted to establish her own reference valves that can be used in her all fifteen branch laboratories instead of using those adapted from the published data or there commended data by the reagent companies supplied as inserts. However, the previous two reference values derived from the statistics(year 2001 and 2002) were need to adjust to apply to actual practice. Besides there was an unavoidable situation that the reagent has to be changed to other companies in 2002 that creates another statistical problem. Subsequently, the third attempt to derive the reference ranges of tests in KAHP to solve those problems and define common)v acceptable reference ranges was done and and reported here. Methods : Al1 the results performed during January 2, 2003 through September 30, 2003 were collected in Excel tile format. All the data include dthe necessary information such as age and sex. The age was grouped in six; baby(0-3y), children(4-l2y), adolescent(13-l8y), adult(19-S4y), younger elderly (65-79y),old elderly(oyer 80y), with references of statistics in medical informatics and WHO classification. The data were statistically analyzed with SAS 6.04 for-Gaussian distribution as the previous two occasions. None of the tests showed Gaussian distribution. These procedures had been repeated twice or three times after trimming out the results lying outside three standard deviations. Though, all the tests showed non-Gaussian distribution. Subsequently, the reference ranges were defined in the range from the point of lower 2.5% to the point of higher 97.5 %. And in case the lower range could be "0", the reference ranges were defined in the range of 0 to 95%.Results : The reference ranges of most of 56 test items were newly assigned. Also with adaptation of the recommendation of WHO etc. on fasting blood sugar, hemoglobin, cholesterol. Among these there were eight tests that needed reference ranges by the age groups and nine tests by the sex. Conclusions : The third attempt will credit more the reference range of all15 laboratories of Korean Association of Health Promotion, which will be essential part of the better service to the patient and clients to visit KAHP.