Ambient ionization mass spectrometry(AIMS) is a mass spectrometry technology which could be used to analyze target analytes in samples under atmospheric pressure without or with simple sample pretreatment.With the advantages of simplicity,rapidness,non destructiveness and wide application range,it is widely used in forensic toxicological analysis.This article gives a brief overview on the ambient ionization(AI) technique,and the samples are divided into two types:in vivo test materials and in vitro test materials.The application of AIMS in the poison analysis of different types of test materials is summarized,and its application direction in forensic toxicological analysis is prospected.