Peter Atke Castberg (born 3 August 1779 in Flekkefjord, died 30 April 1823) was a Danish professor who founded modern deaf education in Denmark. 

In the years 1803-1805 he went on a study trip, to visit schools for the deaf in Kiel, Berlin, Vienna and Paris. After his return, Castberg sends a report to the government, drawing attention to the need to set up a school for the deaf and dumb. The law on this was given by Christian 9. April 17, 1807, after which the official teaching could begin with 10 students at the "Royal Institute for the Deaf and Dumb in Copenhagen".

In front of the institute is a monument in memory of Peter Castberg, made in 1922 by the sculptor Viggo Chr. Hansen.