Marine dinoflagellates are responsible for producing much of marine toxins of fish and shellfish poisons.Especially, the genus Prorocentrum,Amphidinium and Gambierdiscus are distributed worldwide and many species are able to produce toxins potentially accumulated through the food web to cause human illness.From the pharmaceutical point of view, many of those bioactive natural products have potential to become chemical probes or new drug candidates.Pharmacologically activity-screening assays were done on the extracts of our dinoflagellates culture collection.The identification of these dinoflagellate species was based on the scanning and/or transmission electron micrographs and 18S rDNA analysis.