Insects have developed their sophisticated olfactory sensory system to utilize the odor information for foraging, mating and communicating between conspecifics. Recently, the analysis of genes related to olfactory reception has been rapidly progressed, and a lot of olfactory receptor genes have been reported in non-model insects. To identify functions of orphan receptor genes, electrophysiological recording method from olfactory sensory neurons expressing the receptor genes is indispensable. Because it requires sophisticated techniques, researchers who can record the olfactory response from the cognate olfactory sensory neurons are very rare around the world. In this paper, we will introduce an electrophysiological recording method called “Single Sensillum Recording (SSR)” that directly record the olfactory responses from olfactory sensory neurons in single olfactory sensilla in insects. Combinations of SSRs with molecular biological experiments and/or neuroanatomical experiments, it will be helpful for the future analysis of odor transduction mechanisms in insects.