Lestat describes himself as six feet tall. He has blond hair that is not quite shoulder length, and that is rather curly, which sometimes appears white under fluorescent lighting. His eyes are gray-blue, but they reflect the colors of blue or violet easily from surfaces around them. He has a short narrow nose, and a mouth that is well shaped, but has always been slightly large for his face. His mouth can look very mean or extremely generous, but always sensual. He has a continuously animated face. Lestat's fingernails (like those of all vampires in The Vampire Chronicles) look like they are made of glass.

Because of his boldness, enthusiasm, and defiance, Lestat's seniors refer to him affectionately as "The Brat Prince", a title of which he is very fond. He is very vain and concerned with fashion, and will pause mid-narrative to remind the reader what he is wearing. He enjoys performing on stage, which he does as both a mortal actor in Paris and a vampire in his rock band called The Vampire Lestat, that he forms with a group of humans in the 1980s. Lestat is also fond of music; he sings and plays the piano and violin. Although he is illiterate as a mortal man, he learns to read and loves literature as a vampire. In one period of his life, he becomes a hermit and spends every night holed up at home, reading.

The first language that Lestat learns is French, although he "writes" his novels in English. In The Vampire Lestat, he notes that despite his French accent, he speaks English "like a cross between a boatman and Sam Spade" and is fond of slang.

Lestat in the books is bisexual, and has male and female lovers as both a vampire and a mortal. He is attracted to whoever most interests him at the time. Most of his early experiences are with male companions; he himself explains this by saying the women in previous centuries simply were not as interesting as men. Later in the series, Lestat offhandedly mentions that he is frightened of women and finds them extremely and egregiously distracting.

Throughout his long life, Lestat is plagued by common philosophical questions, such as "Are my actions good or bad?", "Is there a God?", "Am I in His plan?", "What happens after death?", and "What makes a person happy?" He finds himself more in love with humanity than ever before, despite his relationship with mankind being savage. For a while, he sees life as "the Savage Garden", filled with beauty and death.

Lestat exhibits a strong altruistic nature at several points in the series. For instance, after he first becomes a vampire, he sends large gifts to his family and friends, purchases the theatre where he once worked, and settles the debts of his old manager, Renaud. Later, after his brothers and family are killed in the French Revolution, he steps forward to care for his ailing father, the only survivor, despite their hateful relationship. Lestat also frequently hunts evildoers instead of feeding from innocent victims, although he does not always abide by this rule.

As a vampire, Lestat's abilities include telepathy, mind reading, superhuman physical attributes, and rapid healing. After receiving blood from several ancient vampires, including Magnus, Marius de Romanus, and Akasha, Lestat's strength increases dramatically and allows him to fly, perform feats of telekinesis and pyrokinesis, and survive exposure to the sun. After Lestat ate the brain of Mekare, he was infused with the spirit of Amel and became the Host of the Sacred Core.

Although he is painted as an anti-hero in Interview with the Vampire, he is quick to defend his own behavior. In The Vampire Lestat, he spends much of the book telling people he is hardly the monster previous narrators have made him out to be. In much of the book, (and its follow up, The Queen of the Damned), he is instead painted as a fun-loving anti-hero who is complicit in the destruction of Akasha, the vampire queen. He loved her completely yet did not agree with her fundamental viewpoint on "morality", leading to her demise.