Magnus Johansen (1 December 1886 - 23 September 1970) was a Norwegian politician for the Labour Party.
He was born in Drammen.
He was elected to the Norwegian Parliament from Østfold in 1937, and was re-elected on one occasion. He had previously served in the position of deputy representative during the terms 1928 - 1930 and 1934 - 1936.
Arntzen was a member of the executive committee of Tune municipality council from 1913 to 1940 and of the municipality council from 1963 to 1967.