The mineral waters that come from the springs in the area of Romanian mountain resort Slanic Moldova, heterogeneous from a physical-chemical point of view, are used for external or internal therapeutic purposes. A survey of the microbiological quality of mineral waters collected from 7 springs in Slanic Moldova was conducted concerning the seasonal quantitative variation of the total number of heterotrophic bacteria (HPC) and the evolution of some representative microbiological parameters (HPC, Clostridium perfringens and Pseudomonas aeruginosa) in samples bottled and stored at (20 - 22 °C) or (4 °C). for a period of 1 - 360 days. All values for HPC determined at 22 °C were within the reference limits of 100 CFU·mL-1 for the investigated sources, in accordance with the requirements of EU and national regulations. At 37 °C, the HPC was within normal values (20 CFU/mL), for five (1 bis, 5, 10, 14 and 15) of the seven sources studied, both in the seasonal analysis and after bottling and storage in different conditions. Clostridium perfringens and Pseudomonas aeruginosa were not detected in all of the mineral water’s samples. Microbiological assessment and proper management of mineral water resources can lead to a good prediction of water quality and avoidance of health risks.