There is still the need for efficacious therapies for pain. In the search for new therapeutic options, plants are a major source of novel biomolecules. Monoterpenes constitute 90% of essential oils, and there is a growing interest in understanding the mechanisms underlying their pharmacological activity. This systematic review reports what is so far known about the analgesic activity of monoterpenes and also provides an overview of their mechanisms of action. The search terms analgesia, anti-inflammatory, anaesthetic and antioxidant were used to retrieve English language articles in SCOPUS, PUBMED and EMBASE published between 1990 and 2012. Forty-five papers were found concerning the potential analgesic activity of 27 monoterpenes. The data reviewed here suggest these compounds are possible candidates for the treatment of painful conditions. Copyright © 2012 John Wiley & Sons, Ltd.