It was first described in 1864 by the American marine zoologist Alexander Agassiz as Toxocidaris depressus, having been collected during the North Pacific Exploring and Surveying Expedition undertaken by Captain Cadwalader Ringgold and later Captain John Rodgers.

The tubercles are numerous and even in size, and the spines are fine and short, their diameter being about a quarter of their length.

[3] As is the case with most other sea urchins, the sexes are separate in this species, and adults liberate eggs and sperm into the water column.

[4] Metamorphosis is stimulated by the detection by the larvae of suitable locations to settle on the seabed, cues being provided by the presence on the substrate of films of micro-algae or of microbes.

[5] Pseudocentrotus depressus is used for human consumption and is the most important species of sea urchin in the southern Japan fishery.