Abstract: The present invention relates to a system for temperature control within an automatic biological analyzer, the automatic analyzer essentially comprising: support, guidance, and step-by-step transport means for reaction cuvettes on a path comprising a predetermined number of positions, a support turntable for analyte samples, a support turntable for reactants, means for taking defined quantities of samples and reactants and for injecting the same into the reaction cuvettes, means for washing the cuvettes, means for optical reading of the determination results and a computerized control system which permits carrying out pre-programmed analysis cycles.