Luigi Galvani (/ɡælˈvɑːni/ gal-VAH-nee, US also /ɡɑːl-/ gahl-, Italian: [luˈiːdʒi ɡalˈvaːni]; Latin: Aloysius Galvanus; 9 September 1737 – 4 December 1798) was an Italian physician, physicist, biologist and philosopher who studied animal electricity. In 1780, using a frog, he discovered that the muscles of dead frogs' legs twitched when struck by an electrical spark. This was an early study of bioelectricity, following experiments by John Walsh and Hugh Williamson.

Luigi Galvani was born to goldsmith Domenico Galvani and Barbara Caterina Foschi, in Bologna, then part of the Papal States. A portion of his childhood home still stands in the Giardino Salvatore Pincherle.

In 1759, Galvani graduated with a degree in medicine and philosophy and began to practice medicine at nearby hospitals. He published his first work, a paper on the anatomy and physiology of bones, in 1762, when he was 25 years old. Galvani presented the work at the Archiginnasio di Bologna, which allowed him to start lecturing at the Academy of Sciences of the Institue of Bologna (now part of the University of Bologna) where he taught anatomy for most of his career.

In 1766, Galvani was appointed curator of the anatomical museum by the senate of Bologna. This position "required him to give lectures and demonstrations of anatomical operations before surgeons, painters and sculptors." In 1782, he was appointed Professor of Obstetric Arts, which he remained for the next 16 years.

Galvani then began taking an interest in the field of "medical electricity". This field emerged in the middle of the 18th century, following electrical researches and the discovery of the effects of electricity on the human body by scientists including Bertrand Bajon and Ramón María Termeyer in the 1760s, and by John Walsh and Hugh Williamson in the 1770s. The publication in 1791 of Galvani’s main work (De Viribus Electricitatis in Motu Musculari Commentarius), summarizing and discussing more than 10 years of research on the effect of electricity on animal preparations, had an enormous impact on the scientific community and sparked heated controversy in Europe.

Alessandro Volta, a professor of experimental physics in the University of Pavia, was among the first scientists who repeated and checked Galvani’s experiments. At first, he embraced animal electricity. However, he started to doubt that the conductions were caused by specific electricity intrinsic to the animal's legs or other body parts. Volta believed that the contractions depended on the metal cable Galvani used to connect the nerves and muscles in his experiments.

Every cell has a cell potential; biological electricity has the same chemical underpinnings as the current between electrochemical cells, and thus can be duplicated outside the body. Volta's intuition was correct. Volta, essentially, objected to Galvani’s conclusions about "animal electric fluid", but the two scientists disagreed respectfully and Volta coined the term "Galvanism" for a direct current of electricity produced by chemical action.

Since Galvani was reluctant to intervene in the controversy with Volta, he trusted his nephew, Giovanni Aldini, to act as the main defender of the theory of animal electricity.