Biological variability is the natural fluctuation of the analyte around the homeostatic point which contributes to uncertainty in the interpretation of the obtained results. Variations of an analyte in a certain individual around the homeostatic point is called intraindividual biological variability, and variation of homeostatic points of individuals in a group of reference population around the average value of the same analyte is called interindividual biological variability. The specifications of the components of biological variability contribute to the definition of analytical quality goals, the selection of the appropriate sample, the appropriate units for expressing the results, and the most appropriate way of interpreting the findings. The aim of this research was to determine the components of biological variability for AMH, inhibin B and androstenedione tests. Forty women of reproductive age, ranging from 19 to 42 years, participated in the research. Samples were taken in three consecutive menstrual cycles, on the 2nd or 3rd day of the cycle. The values of total variability (CVT), analytical variation (CVA), intraindividual variability (CVI) and interindividual variability (CVG) were determined for each analyte. The following results were obtained for AMH: CVT of 16.0%, CVA of 4.6%, CVI of 15.3% and CVG of 67.7%. CVT of 18.1%, CVA of 2.1%, CVI of 17.9% and CVG of 41.2% were obtained for androstenedione. CVT of 34.5%, CVA of 26.1%, CVI of 33.1% and CVG of 42.4% were obtained for inhibin B. For AMH and androstenedione tests, it was determined that biological variability contributes more to the variability of results than analytical variation, which should be taken into account when interpreting results. For inhibin B test, the total analytical variation is less than the total intraindividual variability, but in some subjects the analytical variation exceeded the intraindividual component, therefore the test did not meet the minimum quality specifications for imprecision.