Multiunit Recording (MR) and Gas Chromatography-MR (GC-MR)  are very important and cutting-edge electrophysiological techniques to study insect neuronal responses to odorants in chemical ecology, playing a role key in studying the mechanisms of insect olfactory reaction to plant volatiles and sex pheromones and in sensitively selecting bioactive compounds. This paper introduced the basic principles, experimental protocols and examples of the two techniques, and further, illustrated the attentions in the applications.