An aromatic ring is extremely stable due to its large resonance energy. Generally, benzylmetallic species react with electrophiles easily at the benzylic position. Another possible reaction site of benzylmetallic species would be their ortho-positions. However, such reactions at the ortho positions have rarely been employed, especially in a catalytic fashion. This review highlights catalytic ortho-functionalizations of styrene derivatives through dearomatization of benzylcopper intermediates which are obtained by addition of copper species to styrenic double bonds.