An automatic analysis apparatus is disclosed which provides for various analytical operations in clinical diagnosis and experiments including measuring the changes in light absorbance of a large number of samples mixed with different reagents in a progressive manner, biochemical, electrolytical, fluorescence, and immunological analysis and EIA analysis of samples in bead solid phase. A plurality of samples are maintained, together with diluents and emergency samples, in an ordered sequence on a sample table rotatably disposed which is rotated by drive means in a stepping manner to move the samples progressively to a predetermined suction position at which a sample pipetter picks up a measured amount of sample and dispenses it to one of a plurality of reaction containers that are arranged in an ordered sequence on a reaction table rotatably disposed, preferably about said sample table. A first and a second reagent table are provided, each carrying a plurality of reagents different in kind from one another, selected for various analyses to be performed. A first and a second reagent pipetter are provided and operated to pick up a measured amount of a particular reagent and mix it with any selected sample in the reaction containers. Each sample and reagent mixture may be scanned to measure the rate of light absorbance during a period of time as the reaction containers is rotated on the reaction table a photometer system including a rotating frame carrying thereon filters for different wavelengths through which the optical beam from a light source is passed to traverse the reaction container to be sensed by an optical sensor as the reaction container is rotated. Each reagent pipetting tube is provided with agitator means which is operated, after each dispensing operation of the pipetting tube into the reaction container, to stir the mixture in the reaction container into a homogenous state for proper reaction.