The aim of this study was to develop an in vitro test for the detection of in order to replace the rabbit test. Recently the human whole blood was assessed for tumor necross factor (TNF) α for the probability of the novel test. When human whole blood is incubated in the presence of reference standard endotoxin, they secrete “endogenous pyrogen TNF α determined by ELISA after a fixed incubation time (6 hours). These results show that the correlation coefficient is greater than or equal to 0.980 in the range of 0 32EU/ml-200EU/ml between the TNF α and the endotoxin. The same result has got from the other kind endotoxin with equal effect in the LAL/TAL test. Therefore we think this human whole blood assay will serve as aternative test.