Abstract The first record of harmful algae bloom (HAB) in Sabah was in 1976 where 202 victims were reported to be suffering from Paralytic Shellfish Poisoning (PSP) and 7 deaths. The causative organism was Pyrodinium bahamense, a dinoflagellate which produces saxitoxin. Since then, Department of Fisheries Sabah has been doing monitoring to safeguard seafood safety, especially shellfish harvested for food consumption. Cochlodinium polykrikoides bloom for the first time in Sabah in year 2005 where Kota Kinabalu and Tuaran experienced fish kill. Since then, other HAB species such as Gymnodinium catenatum, Gonyaulax polygramma and Noctiluca scintillans were identified in waters of Sabah. Sabah is the only state in Malaysia in which the monitoring program is done consistently throughout the year since 1976. Samples were collected once or twice a month, according to high and low risks areas which have been identified, most of which are in the west coast. The collection frequency may be increased depending on the situation such as whether there is an outbreak of red tide or PSP in the area. Due to this effort, PSP cases involving the public have declined during the last 40 years without duly affecting the income of fishermen and the fisheries industry. After successfully implementing toxin monitoring between 1984 to 2013, it recurred back in 2013 when 3 deaths were reported. The purpose of this paper is to review all HABs incidences that occured in Sabah over the last few years from January 2000 – December 2017.