John Kenneth Bartlett (7 December 1945 – 1 May 1986) was a New Zealand plant collector and botanist who specialised in mosses, liverworts, and lichens.

On his return to New Zealand, Bartlett worked as a teacher at Auckland Grammar School and at Sacred Heart College where, at his death on 1 May 1986, he was Head of Science.

The speed at which he collected plants, and his capacity to cover large areas of unvisited country led him being given the nickname "Hurricane Bartlett".

In 1985, a new family of mosses, the Hypnobartlettiaceae, was named in his honour (based on specimens he collected in North West Nelson).

While searching for liverworts in 1975, Bartlett came across an unusual species of rātā growing at Radar Bush, 9.5 km south-east of Cape Reinga.

His attention was drawn to the tree's distinctive bark, which is spongy, whitish and flakes easily, but he was unable to reach any branches.