Gustav Adolph Ackermann (16 January 1791 – 19 February 1872) was a German lawyer and author of a notable book on European knightly orders.
Ackermann was born in Auerbach in Vogtland, Electorate of Saxony, Holy Roman Empire.
He was Königlich Sachsischer Appelationsrat [Royal Saxon appeal councillor] at the courthouse in Dresden, Saxony and a great connoisseur of the 19th-century and medieval German and European knightly orders.
In 1855 his Ordensbuch [Orders book] appeared in Annaberg with the subtitle Sämtlicher in Europa blühender und erloschener Orden und Ehrenzeichen [Complete gathering of flourishing and extinct orders and honorific decorations in Europe].
Despite its title, the book is not a complete description of orders and decorations, but it is a valuable resource for researchers.