Wilhelm von Beetz (27 March 1822 – 22 January 1886) was a German physicist, known for his studies of electrical conductivity properties.

He studied physics, chemistry and physiology in the University of Berlin, and after completion of studies, remained in Berlin as an instructor of physics at the Cadet Corps, followed by duties as a teacher at the artillery and engineering school.

In 1868 he became a professor at the Technical University of Munich, where in 1874 to 1877 he was director.

In 1869 he became a member of the Bavarian Academy of Sciences, and in 1882 was named president of the Internationalen Elektrizitäts-Ausstellung (International Electricity Exposition) in Munich.

He best known work was Leitfaden der Physik (4th edition, 1872), a textbook of physics that was published over numerous editions.