PURPOSE: To automatically detect whether the test when the quantity of endotoxin is measured is valid and whether the preparation of products is proper, and to check necessary conditions for starting the test before the measurement is started thereby to completely avoid waste brought about if the measurement is tried again.

CONSTITUTION: The apparatus is provided with a preserving means 5 for preserving at least the arrangement of kinds of samples of specimens and comparison specimens, means 9, 14 for measuring the reaction of a to-be-inspected sample which is a mixture of the specimen or comparison specimen with a reagent thereby generating a measuring value, means 6, 7, 8 for preserving conditions to execute calculations to the measuring value of the to-be-inspected sample, and means 10, 11 for inputting a predetermined data to each preserving means. Further, the apparatus has judging means 3, 4 and means 12, 13 for outputting the result of tests. Each judging means 3, 4 suitably combines the contents of the preserving means in accordance with the kind of a test, detecting necessary conditions for starting the test, performing calculations from the measuring value and the content of each preserving means and judging the validity of the test and whether the calculated value is proper.