The dilithium sequencer was a type of engineering equipment in the 22nd and 23rd century. This electrically powered device was responsible for determining the order in which a series of operations involving dilithium were performed.

In September 2152, T'Pol had problems with the dilithium sequencers aboard Enterprise NX-01 which caused a delay in shutting down the warp engine. (ENT: "The Catwalk")

In 2286, Montgomery Scott converted the sequencer on board the HMS Bounty to something that was "...less primitive." (Star Trek IV: The Voyage Home)