Andreas Hornbeck Isachsen (31 May 1829, Grimstad - February 22, 1903, Cologne) was a Norwegian actor and playwright.
[1] In 1850, still a student, Isachsen briefly edited the student-society newspaper Samfundsbladet alongside the future playwright Henrik Ibsen.
He resumed acting in 1860 at the Christiania Norwegian Theatre, then under Ibsen's artistic direction.
In 1865 he returned to the Christiania Theatre, but joined Bjørnstjerne Bjørnson's walkout to the Folketheater at Møllergaten, where he acted from September 1870 to February 1872.
Isachsen argued with Ibsen over an 1873 play reading of Emperor and Galilean held at Christiania on his own initiative.