Amandus Heinrich Adamson (12 November 1855 in Uuga-Rätsepa, near Paldiski – 26 June 1929 in Paldiski) was an Estonian sculptor and painter.
Born into a seafaring family, Adamson excelled in wood carving as a child. He moved to St. Petersburg in 1875 to study at the Imperial Academy of Arts under Alexander Bock. After graduation he continued to work as a sculptor and teacher in St. Petersburg, with an interruption from 1887 through 1891 to study in Paris and Italy, influenced by the French sculptors Jules Dalou and Jean-Baptiste Carpeaux.
Adamson produced his best-known work in 1902. His Russalka Memorial, dedicated to the 177 lost sailors of the Ironclad warship Russalka, features a bronze angel on a slender column. The other work is architectural. His four allegorical bronzes for the Elisseeff department store in St. Petersburg (for architect Gavriil Baranovsky), and the French-style caryatids and finial figures for the Singer House (for architect Pavel Suzor) are major components of the "Russian Art Nouveau" visible along Nevsky Prospekt.
He was named an academician of the Imperial Academy in 1907. In 1918, in the context of the Russian Revolution and the Estonian War of Independence, Adamson returned to his home town of Paldiski in northwestern Estonia, where he spent the rest of his life.