Chronic pain represents a major clinical issue which so far is still in shortage of selective and effective treatment. Multiple components are involved in the pain processing, including peripheral, spinal and supraspinal levels of the nervous system. The core to fight the pain problem effectively is to have a good understanding of nociceptive mechanism and the neurobiology of pain perception. Optogenetic technique allows selective activation of subpopulation neurons and provides possibility for better understanding of complex pathway and modulation mechanism in nervous system. Here we review the researches to date that used optogenetic tools for studying pain pathway, and we also provide a brief overview of some new development in optogenetic techniques that may have great potentials in pain research.