The coastal waters of China Seas have observed many harmful algal blooms (HABs) caused by dinoflagellates such as Karenia mikimotoi, Prorocentrum donghaiense, Karlodinium veneficum, and Cochlodinium polykrikoides in the last decades and the associated catastrophic losses in shellfish aquaculture, fisheries and coastal ecosystems. In the view of addressing these problems, we revew the advancements in our knowledge about the characteristical life history and in particular, resting cysts, of dinoflagellates, because cysts have been shown to be associated with genetic recombination; resistance to unfavorable environmental conditions; protection from viruses, grazers, or parasite attacks；termination of algal blooms；seeding recurrent HABs; and geographic expansion of populations via ships'' ballast water, which, together, proves that resting cyst plays a central role in the ecology of HABs caused by dinoflagellates. We reviewed and discussed 1) the complexity of life cycles of dinoflagellates and controversies in the definitions and categorization of cysts, 2) the importance of cyst mapping in sediments in forcasting blooms and the associated complexity in the coupling between cyst abundance/distribution and the magnitude of blooms, 3) the complexity of factors affecting encystment and excystment, and 4) the recent progresses in genomic and transcriptomic studies on dinoflagellates in general and cyst-relevant molecular mechanisms in particular, and the possible vital roles of phytohormone in cyst-relevant processes. After a brief summary of the landmarks along cyst-relevant studies in the international HAB community and China, we end the revew by highlighting four research themes about the life history and cyst-relevant issues in China, namely, 1) more comprehensive investigations on an inventory of dinoflagellate cysts in the coastal sediments of China Seas and on the life histories of those important HAB species in China, 2) more intensive investigations on the species of cysts carried in those ships arriving ports of China and assessments of possible bioinvasion of alien HAB species via ships'' ballast water, 3) more field investigations on the processes in encystment, excystment, and coupling between life history events and bloom dynamics, and 4) investigations on the molecular processes relevant to encystment, dormancy, and excystment via a combined approach of -omics and physiology, as well as applications of different molecular probes for detecting HAB species and particular types of cells pertinent to bloom dynamics.