Otomo Nin Dinomaru is an auxiliary mecha from Shuriken Sentai Ninninger (2015). The series' mechs are called Otomo Nin (companion ninja); Dinomaru is orange and modelled on a Tyrannosaurus. Unlike the team's regular Otomo Nin, it does not come from the TV series but from the summer film Shuriken Sentai Ninninger The Movie: The Dinosaur Lord's Splendid Ninja Scroll! (2015). In the story Dinomaru originates from a castle lord who is cursed into a dinosaur form and, after his horn is broken, separates from the curse and joins the Ninninger as an ally. Ninninger was adapted into Power Rangers Ninja Steel / Super Ninja Steel, but Dinomaru never appeared in that version: as a Japanese theatrical-exclusive mecha it had no screen time in Ninja Steel and received no Bandai America or Hasbro toy.

In dinosaur mode Dinomaru fights with bites, claws and a drill-tipped tail, and it can also rise into a humanoid form that fires from shoulder-mounted launchers. Like every Otomo Nin it is summoned through its own shuriken and docks onto the separately sold main Megazord DX Shurikenjin. The result is Shurikenjin Dino, the strongest configuration of Shurikenjin, armed with the Dino Drill and the Dino Hammer.

The DX toy was released by Bandai Japan as Otomo Nin Series EX Dinomaru on 8 August 2015 to coincide with the film, at a retail price of 4,180 yen. Like the rest of the Otomo Nin line it is predominantly plastic, and it is a redeco/retool of the Otomo Nin Paonmaru (elephant) mould, sharing that figure's beast-to-humanoid transformation. The set includes the matching Otomo Nin Shuriken (Dinomaru); forming Shurikenjin Dino requires the separately sold DX Shurikenjin. As a movie tie-in EX release, Dinomaru is one of the harder-to-find Ninninger side pieces.