Nanotechnology is still in its infancy, as it has become a hot area only a few years ago. However, nanotechnology is expected to dramatically change operating characteristics of chemical sensors and will probably gain in importance in all fields of sensor application over the next ten to twenty years. An electronic signal in the form of noise can trace highly volatile chemicals in foods, drugs, and especially in air/atmosphere, but it is still very much a challenge to detect the odours from crystalline compounds with a low vapour pressure using the present chemo sensing techniques. The analysis of explosives is also of interest in forensic research, land mine detection and in the study of environmental problems associated with explosive residues. Based on that the portable sensor can carry on any crime scene or spot and detect the explosive chemical on site. Through the help of the sensor, hazardous materials can also be found in water and other food beverages. The use of sensors by human being has been day by day increasing at an astounding rate in the last few years and modern society depends heavily on the use of the sensors for variety of purposes, such as detection of smoke, radiation and gases. There is no doubt that there will be increasing demand for newer and better chemical and biological sensors in the future. History has shown that advancements in materials science and engineering have been important drivers in the development of sensor technologies. In this chapter, it explains the different types of senor and how the sensors can detect nitroaromatic and other explosives. It is also explaining the fluorescent based detection of explosive materials. This type of chemosensor can be very fruitful to forensic defence and for food industry. The chapter is mainly focuses on the detection of the explosive materials and which type of materials can be useful for fabricating the different types of the chemical sensors based on the applications accordingly.