This study was conducted to investigate the effect of repeated blood collection on the amount of vitamin E in serum and liver of the rats fed standard diet. Rats (Sprague Dawley strain) were fed standard were fed standard diet for several weeks. Blood was collected with on improved cardiac puncture method at regular intervals . The amount of vitamin E analogs were measured by the HPLC. 1) The growth curve of all groups was normal, but bodyweight gains of group II were significantly decreased in case of 7 week- rats whose blood was collected at intervals of two weeks. 2) The amount of vitamin E analogs in serum of rats during growth increased, but continuos blood collection could not affect on the amount of vitamin E in serum. Especially, in the group I serum vitamin E equivalent were significantly higher in case of 7 weeks than first week. 3) The amount of liver vitamin E analogs were changed irregularly, and especially, $alpha$-Tocopherol equivalent were significantly higher in group II then other groups.