Johannes or John Waterstradt (8 March 1869 – 1944) was a German-born Danish natural history collector and mineral prospector in Southeast Asia.
He collected birds, orchids, butterflies and moths from the Papua New Guinea and Indonesian regions for several European collectors including Otto Staudinger and Hans Fruhstorfer.
In 1895 he began to consider an import-export business from Palawan, prospecting for minerals and coal while also collecting natural history specimens.
In 1899 an attempt on his life was made which Waterstradt attributed to Enche Musim, possibly related to oil concession agreements with the Sultan of Brunei.
In 1904, Waterstradt returned to Europe and married Laura Fritzberger and managed the family garden business while also growing orchids that he had collected which he began to sell.