Abstract: N-acetyltransferase (NAT) is an important enzyme of phase Ⅱ drug metabolism of the body, it also plays a vital role in drug metabolism and noxious substances detoxification. NAT's activity differs markedly among individuals and races, which may be responsible for the different herapeutic effect and toxic reaction of certain drugs. NAT's activity can be used to evaluate the ability of acetyl metabolism and drug disposition. This review systematically summarized the methods for NAT activity assay by consulting literatures and the related information, the features as well as strengths of the described methods for NAT activity assay are also summarized here. This present review may provides methodological evidence for NAT activity evaluation, it may also provide a novel basis for personalized drug therapy in clinical.