Denebia was an unaligned Class M planet proximate to both the Federation and the Klingon Empire in 2270. It was the homeworld to a humanoid race known as Denebians.

The Klingon Krong was exiled to Denebia following his dishonorable killing of his commanding officer, M'kar.

Leonard McCoy and Montgomery Scott spent a day in the city of Meekrab on Denebia in 2270, after being dropped off by the USS Lexington to await the arrival of the USS Enterprise. (TOS short story: "Where Everybody Knows Your Name")

Denebia is distinct from Deneb V, and is not a part of the Deneb system. It is also described as the place where Denebian slime devils come from, though that may be in reference to the drink rather than the animal.

planets visited by the USS Enterprise (NCC-1701) during Captain Kirk's initial five-year mission (2265-2270)
various	Capory
2265	Earth • Draxis II • Tally • Alpha Ortelina VII • Arronus VII • Aldebaran III • M-155 • Mestiko • Tally • Dimorus • Tendar • Archernar IV • Delta Vega I • Miri's homeworld • Starbase 12 • 7348-II • robot planet • Timshel • K-G • Zarta • Metamorpha • Numero Uno • FP-1 • FP-2 • Voodoo planet • Gamma Alpha V • Starbase 8 planet • Pollux II • Dukar • Neesan • Algenib II
2266	Beta IV • Rigel XII • Psi 2000 • Tlaoli IV • Alpha Proxima II • Angira • Exo III • 1324-IV • Canara • Nador • M-113 • Alfa 177 • Planet Q • Benecia • Starbase 11 planet • Talos IV • Numero Uno • Gateway
2267	Makus III • Beta VI • Janus VI • Omicron Ceti III • Deneva • Ceti Alpha V • Eminiar VII • Babel • Gamma Canaris 527 • Taurus II • Hydra Epsilon III • Ximega II • Perseus Arm planetoid • Starbase 11 planet • Salvum • Grotus • Rifas-L • Amusement Park planet • Heitius VII • Centaurus V • Tyrtaeus II • Gothos • Cestus III • Iron-silica planet • Zutotanium planetoid • Mudd • Earth • Canara • Beta III • Pyris VII • Vulcan • Pollux IV • Argelius II • Halka • Bavarya • Neolithia • Mythra • Capella IV • Magna Roma • Gamma Trianguli VI • Sigma Iotia II • Masaba • Lekythos • Shroud IV • Tycho IV • Donico II • Rimillia • Organia
2268	Narnel's World • Neural • Fornax II • Gamma II • Triskelion • Argus X • Tycho IV • Signi Beta • Earth • Direidi • Eeiauo • Patria I • Leora IV • Academy • Delta Canaris IV • Alnath II • Ammdon • Marcos XII • Amerind • Beta XII-A • Elas • Troyius • Sigma Draconis VI • Ekos • Scalos
2269	Anomaly • Excalbia • Andros • Pollux V • Avalon • Camus II • Tanis • Aleph Prime • Kyros • Viden • Theta Tau V • Aleph III • Trefolg • Mantilles • Merak II • Ardana • Babel • Organia • Gateway
2270	Isitra Zero • Gateway • Mercan • Denebia • Phylos II • Amusement Park planet • Motherlode • Megas-Tu • Terratin • Sherman's Planet • Argo • Vedala asteroid • Dramia II • Arret • Lactra VII • Delta Theta III • Archernar IV • Cenotaph • Taygeta V • Okeanos • Yoondri • Aleriad • Mercan • Aritani • Yalbo • Sycorax • Talos IV • Earth • Starbase 12 • Tomarii