Other than the first-person narrator "Henry Miller",:108 the major characters include:
- A friend who rents rooms at the Villa Borghese.:22–23 The character was modeled after Michael Fraenkel, a writer who "had sheltered Miller during his hobo days" in 1930.:103,176
- A writer friend who complains about optimistic people, about Paris, and about writing.:49–50 Miller helps Carl write love letters to "the rich cunt, Irene", and Carl relates his encounter with her to Miller.:107–117 Carl lives in squalor and has sex with a minor. The inspiration for Carl was Miller's friend Alfred Perlès, a writer.:10
- A sailor who befriends Fillmore and Miller.:194–208 As Collins had fallen in love with a boy in the past, his undressing a sick Miller to put him to bed has been interpreted as evidence of a homoerotic desire for Miller.
- A "young man in the diplomatic service" who becomes friends with Miller.:193 He invites Miller to stay with him; later the Russian "princess" Macha with "the clap" joins them.:219–238 Fillmore and Miller disrupt a mass while hung over.:259–263 Toward the end of the book, Fillmore promises to marry a French woman named Ginette who is pregnant by him, but she is physically abusive and controlling, and Miller convinces Fillmore to leave Paris without her.:292–315 Fillmore's real-life counterpart was Richard Galen Osborn, a lawyer.:46
- A character corresponding to Miller's estranged second wife June Miller.:96–97 Miller remembers Mona, who is now in America, nostalgically.:17–21, 54, 152, 177–181, 184–185, 250–251
- A woman married to Sylvester.:56–57 The character was modeled after Bertha Schrank, who was married to Joseph Schrank. It may also be noted that during the writing of the novel, Miller also had a passionate affair with Anais Nin; by changing the "T" to an "S", one can make out Anais from Tania by rearranging the letters. It may also be noted that in one of Nin's many passionate letters to Miller, she quotes his swoon found below. Tania has an affair with Miller, who fantasizes about her:
O Tania, where now is that warm cunt of yours, those fat, heavy garters, those soft, bulging thighs? There is a bone in my prick six inches long. I will ream out every wrinkle in your cunt, Tania, big with seed. I will send you home to your Sylvester with an ache in your belly and your womb turned inside out. Your Sylvester! Yes, he knows how to build a fire, but I know how to inflame a cunt. I shoot hot bolts into you, Tania, I make your ovaries incandescent.:5–6
- Van Norden
- A friend of Miller's who is "probably the most sexually corrupt man" in the book, having a "total lack of empathy with women".:25–27 Van Norden refers to women using terms such as "my Georgia cunt", "fucking cunt", "rich cunt", "married cunts", "Danish cunt", and "foolish cunts".:100–107 Miller helps Van Norden move to a room in a hotel, where Van Norden brings women "day in and out".:117–146 The character was based on Wambly Bald, a gossip columnist.