ABSTRACT: One of the elementary requirements of the Council Directive 91/676/EEC (Nitrate Directive) is to designate and regularly review Nitrate Vulnerable Zones for identification of nitrate-polluted waters from agricultural sources and waters which could be affected by this pollution if action is not taken. It is therefore necessary to monitor groundwater and surface water quality in these areas and implement Action Programs to prevent and reduce water pollution by nitrates from agricultural sources. This paper presents the methodological procedure and results of the 2016 Nitrate Vulnerable Zones revision enforced in the new Government Regulation of the Slovak Republic No. 174/2017 Coll. which establishes sensitive areas and vulnerable zones. Our assessment complied with Nitrate Directive requirements; with 264 of the total 1,561 Nitrate Vulnerable Zones proposed for exclusion and 47 areas introduced into Nitrate Vulnerable Zones. As a result, the total Nitrate Vulnerable Zones in the Slovak Republic decreased by 217 municipalities to 1,344.