Littoral and epibenthic, ranging from river mouths and bays to continental shelf and slope waters. Usually found in depths of 0 to 1,200 m, but one shark was observed at 2,200 m off North Carolina (Herdendorf and Berra 1995, Compagno in prep. a). During winter months in the Arctic and boreal Atlantic, the species occurs in the intertidal zone and at the surface in shallow bays and river mouths, moving into depths of 180 to 550 m during warmer months. At lower latitudes (Gulf of Maine and North Sea) the species occurs on the continental shelves with possible movements into shallower water during spring and summer (Compagno in prep. a). Short term tracking studies of the Greenland sharks under ice off Baffin Island during late Spring suggest that individuals remained at deeper depths during the morning, gradually moving into shallower depths in the afternoon and at night (Skomal and Benz 2004). The species has been recorded in water temperatures of 0.6 to 12°C (Compagno in prep. a).

Maximum size is uncertain, but is at least 640 cm TL, possibly to 730 cm TL, however most adults are between 244 and 427 cm TL (Compagno in prep. a). Aplacental viviparous with one observed female carrying 10 young (Compagno in prep. a). Tagging studies have shown the species to be very slow growing with medium size sharks appearing to grow at a rate of 1 cm per year (Hansen 1957, Castro 1983, Castro et al. 1999).

Although reportedly sluggish, feeds on a variety of prey including invertebrates, fish, seabirds, seals as well as offal (see Compagno in prep. a for more details).

Life history parameters
Age at maturity (years): Unknown.
Size at maturity (total length cm): Unknown.
Longevity (years): Unknown.
Maximum size (total length): 640?730 cm TL.
Size at birth: ~37 to 38 cm TL (Bjerkan and Koefoed 1957, Compagno in prep. a).
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: 10.
Annual rate of population increase: Unknown.
Natural mortality: Unknown.