The deputy prime minister of Luxembourg () is the second-highest position in the government of Luxembourg. The deputy serves a vital function in Luxembourg's collegiate cabinet system, deputises for the prime minister when he is absent, represents their own political party, and holds other government positions.
Since the position was created, in 1959, almost all governments have been coalitions of two of the three major parties: the Christian Social People's Party (CSV), the Luxembourg Socialist Workers' Party (LSAP), and the Democratic Party (DP). The current government consists of the CSV and the DP. The deputy prime minister has always been a leading politician from the junior coalition partner. During Xavier Bettel's second term as Prime Minister (2018-2023), the position was shared by a First and Second Deputy Prime Minister, representing the two junior partners in the coalition respectively (the LSAP and déi Gréng).
Since 1989, the title of Deputy Prime Minister has been an official one, although the position had been unofficially known by that name since its creation. From the position's creation until 1989, the deputy prime minister went by the title of Vice-President of the Government. This mirrored the prime minister's title, which was President of the Government until 1989. The name Vice Prime Minister is also used.