Detection methods of negative and positive ion were rapidly developed for several decades. The kind of ion was plenty and the detection methods were improved. In order to obtain satisfied accuracy and sensitivity, we should choose a suitable method according to difference analysis objective. This article briefly summarized the application of detection methods to negative and positive ion in drugs, such as turbidimetry, colorimetry, titration, ion-selective electrode, ultraviolet-visible spectrophotometry, atomic absorption spectrophotometry, and chromatography, and so on. Finaly, the development trends of the technology have been prospected.