William Botting Hemsley (29 December 1843, in East Hoathly – 7 October 1924, in Kent) was an English botanist and 1909 Victoria Medal of Honour recipient.
He was born in East Hoathly, Sussex and in 1860 started work at the Royal Botanic Gardens, Kew as an Improver, then Assistant for India in the Herbarium, finally Keeper of Herbarium and Library.
He wrote a number of botanical works.
He was elected a Fellow of the Royal Society in June 1889.