Pierre Joseph Auguste Messmer (French pronunciation: ?[pj?? m?sm??]; 20 March 1916 – 29 August 2007) was a French Gaullist politician.
He served as Minister of Armies under Charles de Gaulle from 1960 to 1969 – the longest serving since Étienne François, duc de Choiseul under Louis XV – and then as Prime Minister under Georges Pompidou from 1972 to 1974.
A member of the French Foreign Legion, he was considered as one of the historical Gaullists, and died aged 91 in the military hospital of the Val-de-Grâce in August 2007.