Siegmund Freiherr von Pranckh (5 December 1821, Altötting, Upper Bavaria – May 8, 1888, Munich), descendant of the ancient Austrian noble family Pranckh, originally residentiary in the former March and later Duchy of Styria, was a Bavarian general and Minister of War. Pranckh joined the army in Munich in 1840 from the cadet corps and in 1849 (having risen to captain) worked on the staff of the Generalquartiermeister. He remained in the War Department until 1863 before entering the 3rd Infantry Regiment as an oberst and then in 1865 entered the Lifeguards Regiment, with which he fought in the Austro-Prussian War, participating in the battle of Kissingen and the storming of Nüdlingen. Shortly afterwards, Pranckh (as war minister) and in 1868 reorganised the Bavarian Army.
Immediately after the outbreak of the Franco-Prussian War he rose to Lieutenant General, and prudently and effectively organized the Bavarian army and its munitions after it had suffered considerable losses. He was also significantly involved in the conclusion of the Treaty of Versailles on 23 November 1870. For his achievements he was granted an endowment of 100,000 crowns from the war compensation awards.
In 1872 Pranckh initiated a further army reform. At the start of 1875 he was appointed General der Infanterie and on 4 April 1875 appointed captain-general of the Hartschier guards. As he requested, he was released from leading the war ministry in 1876, and became Generalkapitän of the Hartschier guard.
He is buried in the Old Southern Cemetery in Munich.