Since the first report on the blood triglyceride level of normal korean in 1962, more than 12 authors published their normal value ranging from 78.0~151.0mg% as mean value. In an attempt to establish normal triglyceride level in Korean, the timing of sampling and method of sample preservation were reevaluated in terms of quality control. Although the number of samples and tests were too small to make an unequivocal conclusion, the following results were observed. 1. Plasma triglyceride levels were stable on continuing fasting 12~16 hours, slightly decreased thereafter. 2. Samples kept in room temperature were stable up to 3 days and the triglyceride level dropped moderately on the 5th day. 3. No significant change in plasma triglyceride level was found with freezing up to one month. 4. Significant change in plasma triglyceride level was noted with repeated melting and refreezing of specimen. 5. The probable reasons for marked differences in normal value of plasma triglyceride level were discussed.