Sebastes polyspinius was first formally described as Sebastodes polyspinis in 1933 by the Soviet biologists Anatoly Yakovlevich Taranetz and Peter Alekseevich Moiseev with the type locality given as the Pribilof Islands near Kamchatka in the Bering Sea.

[5] This is a demersal fish which is found at depths down to 740 m (2,430 ft) on soft substrates.

[1] Sebastes polyspinis is a little known species, Like its congeners it is ovoviviparous and the larvae are born from April.

Half of the fish are sexually mature 7.6 years at 27.7 cm (10.9 in), younger than those in the Gulf of Alaska.

[6] Northern rockfish feed mainly on krill with copepods, hermit crabs, and shrimp forming a minor components of their diet.