John Hopkinson, FRS, (27 July 1849 – 27 August 1898) was a British physicist, electrical engineer, Fellow of the Royal Society and President of the IEE (now the IET) twice in 1890 and 1896.

He also worked in many areas of electromagnetism and electrostatics, and in 1890 was appointed professor of electrical engineering at King's College London, where he was also director of the Siemens Laboratory.

In 1877 Hopkinson was elected a Fellow of the Royal Society in recognition of his application of Maxwell's theory of electromagnetism to problems of electrostatic capacity and residual charge.

On 27 August 1898, Hopkinson and three of his six children, John Gustave, Alice and Lina Evelyn, were killed in a mountaineering accident on the Petite Dent de Veisivi, Val d'Hérens, in the Pennine Alps, Switzerland.

[12] His wife Evelyn (née Oldenburg), his two sons Bertram and Cecil, and his daughter Ellen (married James Alfred Ewing in 1912) are buried in the Ascension Parish Burial Ground, Cambridge; the rest of the family are interred in Switzerland.

Cecil (1891-1917) shared rooms with Lawrence Bragg whilst they were both studying at Trinity College, Cambridge and they became firm friends, he incurred a severe head wound in the 1914-19 war and died a few months after being invalided back to the UK.