Photoacoustic spectroscopy is a novel gas detection technology. Photoacoustic spectroscopy is an indirect absorption spectroscopy technology. Gas concentration inversion is performed by detecting acoustic signals. It has the advantages of simple structure, response speed, and small system size. It is one of the widely used high-sensitivity trace gas sensing methods currently under development and is becoming one of the research focus in detecting toxic gases, explosives and chemical warfare agent simulants. This paper focuses on the research work of photoacoustic spectroscopy in the rapid detection of chemical warfare agent simulants and toxic gases. Photoacoustic spectroscopy can use different laser systems. When the laser emission range is in the mid-infrared band, chemical warfare agent simulants will have characteristic absorption peaks in these bands, so they can also be used to detect chemical warfare agent simulants. This paper introduces the methods of photoacoustic spectroscopy in foreign countries for the detection of chemical warfare agents and simulants. It introduces the method information such as the optical path configuration, laser light source, etc. in the method, as well as the structural characteristics of the newly built gas absorption cell. The characteristic absorption wavelength range of photoacoustic spectroscopic detection of chemical warfare agents and simulants was analyzed. In addition to the traditional detection of chemical poisons in gas absorption cells, methods and systems for the open optical path telemetry of photoacoustic spectroscopy in the range of several centimeters to tens of meters have been continuously developed in recent years to detect chemical warfare agent simulants. The article also reported the method of photoacoustic spectroscopy in detecting ammonia, hydrogen sulfide, HF, sulfur dioxide and other toxic and harmful gases. This paper analyzes the related work on light sources and methods, acoustic wave transducers, characteristic spectra of chemical poison simulants, and detection performance. The foreign short-range telemetry photoacoustic spectroscopy prototype is reported, and the potential development of photoacoustic spectroscopy short-range spectral telemetry technology is reviewed.