Since the last century, the richness of the Canary Islands marine flora has attracted many botanists. Børgesen's seminal papers have been the main reference source for anyone interested in this flora. The first checklist of the marine macroalgae from the Canary Islands was published by Gil-Rodríguez and Afonso-Carrillo (1980a) with 434 macroalgal species being listed together with some dubious records. In recent years, the research efforts of local phycologists and the output of some scientific expeditions have yielded some new species and a large number of new records to the Canarian seaweed flora. The aim of this contribution is to compile an up-to-date catalogue of the marine plants for the Canary Islands (including cyanobacteria, macroalgae, seagrasses and fungi). The review of all published records of these marine plants takes into account the present taxonomic status and nomenclatural changes of the taxa concerned and rejects old and dubious records. After a careful review of the pertinent references and revision of live and preserved material, only valid records published before July 2001 are included in this checklist. Besides, each species is quoted for the islands in an east-west fashion to illustrate the distributional pattern of the species concerned. The marine flora of the Canary Islands is composed of 711 species, which are distributed as follows: 59 Cyanophycota, 385 Rhodophycota, 125 Chromophycota, 117 Chlorophycota, 3 seagrasses and 22 fungi. Compared to nearby regions, the Canarian archipelago comprises a much larger number of species. This high diversity appears to be the result of the combined effects of its geographic location, paleoclimatic events and the prevailing oceanographic conditions. [ABSTRACT FROM AUTHOR]