In the summer, these sharks migrate towards the poles following cool water masses, sometimes forming schools numbering in the hundreds to thousands.

It is an active predator that takes a wide variety of bony fishes and invertebrates, with larger individuals also feeding on sharks and rays.

This shark is potentially dangerous and has likely been responsible for a few attacks on humans, though it is less likely to encounter swimmers than other large hammerhead species due to its temperate habitat.

The Swedish natural historian Carl Linnaeus, known as the "father of taxonomy", originally described the smooth hammerhead as Squalus zygaena in the 1758 tenth edition of Systema Naturae, without designating a type specimen.

[3] The specific epithet zygaena originates from the Greek word zygòn, meaning "yoke", referring to the shape of its head.

[3] The dermal denticles are densely packed, each with 5–7 horizontal ridges (3 in juveniles) leading to a W-shaped rear margin.

The back is dark brownish gray to olive in color, in contrast to the simple brown of most other hammerheads, becoming lighter on the flanks.

In the Atlantic, it occurs from Nova Scotia to the Virgin Islands and from Brazil to southern Argentina in the west, and from the British Isles to Côte d'Ivoire, including the Mediterranean Sea, in the east.

[3] In Northern Europe, there are only seven confirmed records from the British Isles, all but one (at Banffshire) from the southern part of the archipelago and all but two (in 2004 and 2019) from more than 100 years ago.

[3] Although generally preferring subtropical and warm temperate regions, a study of captures in the West Atlantic and Gulf of Mexico off the United States recorded smooth hammerheads in water temperatures ranging from 7.5 to 27.5 °C (45.5–81.5 °F).

In the summer, smooth hammerheads migrate poleward to stay in cooler water, heading back towards the equator in winter.

[9] The smooth hammerhead is an active-swimming predator that feeds on bony fishes, rays, sharks (including of its own species), cephalopods, and to a lesser extent crustaceans such as shrimp, crabs, and barnacles.

[17] In northern Europe, the smooth hammerhead feeds on herring and seabass, while in North America it takes Spanish mackerel and menhaden.

[9] Off South Africa, smooth hammerheads feed on squid such as Loligo vulgaris and small schooling fish such as pilchard over the deep coral reefs at the edge of the continental shelf, with individuals over 2 m (6.6 ft) long taking increasing numbers of smaller sharks and rays.

[22] However, due to the smooth hammerhead's occurrence in temperate regions where people are less likely to enter the water, it was likely responsible for a minority of these attacks.

[3] Smooth hammerheads are caught by commercial fisheries throughout the world, including those off the United States (East and West Coasts), Brazil, Spain, Taiwan, the Philippines, southwestern Australia, and western Africa, primarily using gillnets and longlines.

[18] At present, this species remains relatively common and has been assessed as "Vulnerable (VU)" by the World Conservation Union.