The identification of Ganoderma species is usually based on classical morphological criteria. The objectives of this review were to collect available information on Ganoderma lucidum and to utilize them in exact identification of Ganoderma lucidum (Fr.) Karst. sensu stricto. A lot of taxonomical confusion has always been associated with G. lucidum and allied species. Species circumscription, phylogenetic relationships, host range and distribution of species of the G. lucidum complex are unclear even among the few taxa living in temperate climate. Several methods have been proposed to identify the species as examination of cultural characteristics, isozymes, secondary metabolites, DNA sequences and interfertility. Although G. lucidumsensu stricto has been reported world-wide accumulated evidence supported the suggestion that it seems restricted to Europe. The strains used in the medicine are usually collected in Asia. There is little likelihood that any one belongs to the G. lucidum sensu stricto. The strains labelled as G. lucidum in the medicinal and pharmacological literature encompass a broad range of species which produce different medicinally active compounds and have significantly different pharmacological effects.