The body of these whales is around 6-7 meters in length. The head is small with a long, narrow beak. The tail fluke is not notched, and the flippers are small and oval in shape. The back is uniform grayish-brown in color, fading to nearly white on the underbelly. Shepherd's beaked whale can be easily distinguished from other members of the family Ziphiidae by the presence of 17-29 conical teeth in both the upper and lower jaw.
Males possess two additional teeth on the anterior most part of the lower jaw.
The blowhole is crescent in shape and is asymmetrically located on the left side of the top of the head. The eye sits directly below the blowhole. These whales eat squid and various fishes. Very little is known about this rarely sighted whale. As of 1996, Tasmacetus shepherdi have been seen alive on only two occasions.