The territory of the Crimean Peninsula has a long history of economic development and as a result, in some, especially old-developed, regions of the Crimean Peninsula, there is a problem of the use of the territory by various nature users and, consequently, nature management conflicts are developing. In most cases, qualitative assessment is used to describe nature management conflicts. The paper shows the possibility of quantifying these conflicts using the concept of an ecological niche in a multidimensional factor space. The paper, based on the concept of ecological niche, provides a quantitative assessment of nature management conflicts in the river basins of the northwestern slope of the Crimean Mountains (the basins of the Zapadnii Bulganak, Alma, Kacha, Belbek, and Chernaya rivers). By nature management conflict we mean a situation when, in a multifactorial space, the ecological niches of the main types of nature use intersect and the quantitative measure of this intersection is the measure of the nature management conflict. For the main types of nature use within the river basins of the northwestern slope of the Crimean Mountains (the basins of the Zapadnii Bulganak, Alma, Kacha, Belbek, and Chernaya rivers), their ecological niches are constructed in the space of the factors “Altitude, m” and “Slope, degrees”, as well as “Annual air temperature, °C” and “Annual precipitation, mm”. A quantitative assessment of the manifestation of nature management conflicts is given as a measure of the intersection of their ecological niches.