Sir William Davidson Niven KCB FRS (24 March 1842 – 29 May 1917) was a Scottish mathematician and electrical engineer.

After an early teaching career at Cambridge, Niven was Director of Studies at the Royal Naval College, Greenwich, for thirty years.

In 1882 Niven became Director of Studies at the Royal Naval College, Greenwich, succeeding Thomas Archer Hirst.

[2] He was appointed a Companion of the Order of the Bath (Civil division) in Queen Victoria's Diamond Jubilee Honours of 1897.

Among Niven's students was Alfred North Whitehead, to whom he taught mathematics, by instructing him in the physics of Maxwell.