Jean Hamilius (born 5 February 1927) is a former Luxembourgish politician and government minister from the Democratic Party. He was born in Luxembourg City. served as Minister for Public Works in Gaston Thorn's government (1974 – 1979). He sat in the Chamber of Deputies between 1969 and 1984 (excepting the five years he spent as a minister), and in the communal council of Luxembourg City (1969 – 1974). He was one of Luxembourg's six Members of the European Parliament from 1979 until 1981.
Hamilius ran at the 1952 Summer Olympics, in Helsinki, in the 400 metres and 4 x 400 metres relay, in an athletics deputation best known for the inclusion of Luxembourg's only gold medalist, Josy Barthel. In 2008 he was promoted to the rank of Chevalier in the Order of Merit of the Grand Duchy of Luxembourg.
He is the son of Émile Hamilius (1897 – 1971), himself a former DP politician and Mayor of Luxembourg City (1946 – 1963), as well as having competed at the Summer Olympics (in 1920), like his son.