The Dwarf People are a race native to Mars. Although not encountered by Flash Gordon or his friends, they are known to the Forest People.
When "Happy" Hapgood tries to explain the operation of his camera to Turan, his suggestion that the image of the Forest King's leader will appear in the small photographic device is misunderstood by the tree dwellers. One of them comments: "Mighty Turan, if the Earthman had pressed that lever you would have become like the Dwarf People and become imprisoned in that magic box!"
This suggests that the Dwarf People may be very small indeed, especially as the Forest People are shorter in height than other Martian races.