Azazel Azazel is the demon that ruined the Winchesters life, when he gave 6 month old Sam his blood to drink and then killed Mary. He set the boys on what seemed like an unending mission to find and kill him. Episodes:- Pilot, Salvation, Devils trap, In My Time of Dying, All hell breaks loose part 1 and All Hell Breaks Loose part 2	Lilith Lilith is the demon who is trying to re-organise Azazel's Army. She wants Sam dead because he is the only competition she has in ruling Hell. Episodes:- Jus in bello, No rest for the wicked.
Ruby Ruby at one time was human. But she sold her soul and went to hell where she became a demon. She is trying to get Sam to use his demon powers to defeat Lilith so that the final seal would be broken and Lucifer would finally roam the earth. Episodes:- The Magnificent Seven, Malleus Maleficarum, Sin City, The Kids Are Alright, Jus in Bello, No rest for the wicked	Meg Azazel's Daughter. She can summon and control Daeva which are really powerful demons. Episodes:- Scarecrow, Shadow, Salvation, Devils trap
Tammi Tammi is a Demon who teaches people witchcraft. Unfortunately for the people she comes into possession of their soul. Ruby was one of Tammi's Converts. Episode:- Malleus Mallificarum	Raksasha A demon that sleeps in filth and can turn invisible and change shape. It eats people. needs to be killed with a bronze stake through the heart. Episodes:- Everybody loves a clown
Tom Tom is Azazel's son and Meg's brother. Episode: Salvation, Devils trap	Duanne Tanner Duanne is also one of Azazel's children. It is possible that Tom and Duanne are the same demon in different humans. Episode:- Croatoan
Deava. Episode: Shadow	Casey Episode: Sin City
Father Gil Episode: Sin City	Crowley Crowley is a high-ranking demon who is known as Lilith's right hand man and becomes the King of Hell after the fall of Lucifer. Episodes: Abandon All Hope..., The Devil You Know, Family Matters, The Man Who Would Be King, Meet the New Boss
Alastair Alastair is probably one of the most powerful archdemon who was sent to capture Anna Milton because no other demons could stop the Winchesters.

Crossroads Demon

This demon is summoned at the crossroads and will grant you a deal in exchange for your soul which it will collect in ten years.
Episodes:- Crossroad blues, All hell breaks loose part 2, Bed time stories

Hell Hounds


These invisible dogs are used by demons to carry out certain jobs. They are used to collect the souls of those who have made a deal with a demon.

Episodes: Crossroad Blues, Time Is on My Side, No Rest for the Wicked