ABSTRACT: Sampling for microbiological parameters of water quality of the Buzgó karstic spring in Krásnohorská Dlhá Lúka (Slovenský kras Mts., Eastern Slovakia) was performed between March 2015 and December 2017, but only eight samples in monthly intervals were taken in 2015, next 65 in approximately weekly interval in hydrological year of 2017. Results were compared to spring’s discharges and meteorological phenomena as precipitation and air temperature courses. The most observable correlation with water stages was found in the cases of microorganism cultivable at 22 °C and 36 °C. Population of these microorganisms was bound to local meteorological phenomena in much lesser extent. Contrary to the results of previous investigations, indicators of faecal contamination were regularly found in Buzgó springs’ water. The influence of high water stages is less observable and is particularly pronounced in growth of enterococci population, in lesser extent also Escherichia coli. No correlation with hydrological data was found for coliform bacteria. Microbiota in the karstic water here is probably mostly influenced by two independent factors: water stage in the underground hydrological system of the Krásnohorská jaskyňa Cave behind the Buzgó spring, and occasional human visits to this system. The second factor mostly influences population of faecal contamination indicators. Results of monitoring also confirmed persisting low population of microorganism cultivable at 22 °C and 36 °C and dominance of the first type of microorganisms in the whole cycle of seasonal changes here.