Abstract: The estimation of the tourist support capacity for three Natura 2000 sites located in North-Westerm Romania and the appropriate use of a quantitative methodology adapted to the current working techniques are the main objectives of this scientific approach. In this respect, parameters were determined for obtaining the physical carrying capacity, then the resulting value was modified by the coefficients related to the correction factors. They also consider CAV_NDVI, a factor reflecting the abundance of vegetation and the value of the NDVI spectral index at pixel level, used to quantify the state of vegetation health, as a measure of the ecological status of the sites. The obtained results highlight the sensitivity of the algorithms used for the correction factors and the possibilities of converting these results into elements with practical possibilities for the sustainable sites management.