John Albert Long is an Australian paleontologist who is currently Strategic Professor in Palaeontology at Flinders University in Adelaide, South Australia.

He was previously the Vice President of Research and Collections at the Natural History Museum of Los Angeles County. He is also an author of popular science books. His main area of research is on the fossil fish of the Late Devonian Gogo Formation from northern Western Australia. It has yielded many important insights into fish evolution, such as Gogonasus and Materpiscis, the later specimen being crucial to our understanding of the origins of vertebrate reproduction.

His love of fossil collecting began at age 7 and he graduated with PhD from Monash University in 1984, specialising in Palaeozoic fish evolution. He held postdoctoral positions at the Australian National University, The University of Western Australia and The University of Tasmania before taking up a position as Curator in Vertebrate Palaeontology at the Western Australian Museum and then as Head of Sciences at Museum Victoria.