Introduction: In the laboratory activity, the quality of testing analysis for determination of the toxic and heavy metals is considered as its ability to ensure the test validity. Improvement of measurement methods, sample preparation for analysis, the introduction of new equipment to improve the quality indicators of services are the most relevant tasks in the activities of testing laboratories. Materials and Methods: With the purpose of comparison of results received by operation on atomic-absorption spectrometer __ampersandsignquot;Quantum-2AT__ampersandsignquot; with use of microwave laboratory system PLP(Pech Laboratory Probopodgotovka)-01M and at sample preparation according to Government Standards(GOST)-26929, four different groups of products were chosen as working samples. These products are fish, bread, milk, meat. Results: The analysis of results of research of samples on the content of lead and cadmium by their determination on atomic absorption spectrometer __ampersandsignquot;Quantum-2AT__ampersandsignquot; with use of microwave laboratory system PLP(Pech Laboratory Probopodgotovka)-01M and sample preparation according to Government Standards(GOST)-26929 is presented. The analysis of the performed studies allowed estimating the time spent on one study taking into account the implementation of different types of sample preparation for analysis. It is established that higher accuracy indicators are achieved in case of microwave decomposition using microwave laboratory system PLP-01M. It is necessary to note a higher level of automation of the sample preparation process in case of application of microwave laboratory system PLP-01M in comparison with the traditional algorithm of sample preparation for analysis according to GOST 26929. Conclusion: It is shown that the validity of the results is determined by several factors: the methods used, the equipment and reagents used, the competence of the personnel, the procedure of internal laboratory control. Using microwave laboratory system PLP-01M for the decomposition of samples before atomic absorption analysis has improved quantitative indicators of quality of the analysis.