The almost complete therapod skeleton was excavated from the Stewartby member of the Oxford Clay Formation, located in the Webb's Brick Pit, Summertown, Oxford. The specimen, now the holotype for Eustreptospondylus oxoniensis was acquired by a local bookseller James Parker in 1870.  The specimen was described in‭ ‬1871 by John Phillips, however he never named it.‭ ‬
       

It has been suggested that there are only minor differences between the hips of Eustreptospondylus and another theropod dinosaur called Magnosaurus,‭ ‬and as such are the same genus.‭ ‬Further support for this comes from similarity in the dentary of the two dinosaurs,‭ ‬however wider consensus at the time of writing is‭ ‬that they are not the same and‭ ‬they both represent their individual groups.