Chapter 1 devoted to the development of biomimetic olfactory biosensors and electronic noses. Authors introduce the mechanism of smell and odor discrimination principles and describe the main components of the olfactory system that are currently used as raw sensing materials for the design of biosensors namely the olfactory receptors and some other proteins such as odorant binding proteins and enzymes involved in biological olfaction. A review on the development of biomimetic olfactory biosensors and bioelectronic noses based on olfactory tissues and cells, olfactory receptors, and odorant binding proteins.