PURPOSE: To enable the analysis of a number of samples for a fixed time length by arranging a carrier or reagent supply passage for transferring a reaction sample to a detector section and a reagent supply passage for injecting samples separately.

CONSTITUTION: An analyzer 1 is equipped with a plurality of reaction passages (tubes) 7, 8 and 9 connected in parallel to a reagent supply section 5 and a reagent injecting section (or an injector) 6 and opening/closing valves 12, 13 and 14 on the upstream of the reaction passages and a detector 11 in that order in a analysis passage 2 and reagent supply passages 15, 16 and 17 are connected to the downstream of the opening/closing valves in the respective reaction passages. With this analyzer 1, separate passage can be used for a carrier liquid to feed a sample into the reaction passages 7, 8 and 9 and a carrier liquid to feed a reaction reagent in these reaction passage to the detector 11. Therefore, a number of samples can be analyzed for a fixed time.