Lyra Belacqua is the novel's main protagonist. She is an 11 year old girl. She is incredibly brave and curious.
Pantalaimon is Lyra's daemon. He is a shape shifter, but he will eventually choose a final form. In the story, a daemon more or less is a physical representation of a character's soul.
Lord Asriel: He's one of the bad guys. Oh, he is Lyra's father too, but she doesn't know that at first. That makes him Lord Vader and Lyra young Skywalker.
Mrs. Coulter: Lyra's mom. She's also evil and has a golden monkey for a daemon.
Iorek Byrnison: He's a big armored bear. He and Lyra work closely together as the novel progresses.
Lee Scoresby: His profession is "aeronaut," meaning he flies hot air balloons. He's also a friend of Iorek's. Pullman paints him as a caricature of an old west cowboy.
"I'm a simple aeronaut, and I'd like to end my days in comfort. Buy a little farm, a few head of cattle, some horses... Nothing grand, you notice. No palace or slaves or heaps of gold. Just the evening wind over the sage, and a ceegar, and a glass of bourbon whisky."
Serafina Pekkal: Queen of the witch clan. She's really old, but looks young. She was in love with Farder Coram.
Farder Coram: He's a "gyptian" elder. He's very smart, and other characters revere his wisdom.
John Faa: Leader of the gyptians.
Other characters are Roger, Ma Costa, and Iofur Raknison.