A Group 8 element is one in the series of elements in group 8 (IUPAC style) in the periodic table, which consists of the transition metals iron (Fe), ruthenium (Ru), osmium (Os) and hassium (Hs).

Like other groups, the members of this family show patterns in its electron configuration, especially the outermost shells resulting in trends in chemical behavior.

"Group 8" is the new IUPAC name for this group; the old style name was "group VIIIA" in the old European system or "group VIIIB" in the old US system. Group 8 must not be confused with the group with the old-style group names of either VIIIB (European system) or VIIIA (US system); that group is now called group 18.

Hassium has not been isolated in pure form, and its properties have not been conclusively observed; only iron, ruthenium, and osmium have had their properties experimentally confirmed. All three elements are typical silvery-white transition metals, hard, and have high melting and boiling points.

Iron has been known and used to make tools since antiquity. Ruthenium was first identified in 1844 in platinum ores, after all other platinum group metals, including Osmium, which was discovered in 1803; by dissolving impure platinum, salts were created. In a graphite-like dust always found in these salts, it was concluded that a new metal must be present, which would be Osmium. Ruthenium was first discovered in the form of ruthenium oxide in a similar manner. Hassium was discovered in 1984 by a team led by Peter Armbruster and Gottfried Münzenberg by bombarding lead-208 with iron-58.