Shifting between multiple perspectives, The Street uses extensive flashbacks to reveal its plot. Lutie Johnson has an eight-year-old son, Bub, to support. Separated but not legally divorced from Bub's father, Jim, Lutie feels that Jim's inability to find employment, her decision to work as a domestic for a wealthy white family in Connecticut, and Jim's subsequent infidelity ruined her marriage.
Lutie moves into a small apartment on 116th Street in Harlem. Taking an immediate dislike to the super, Jones, she decides to take the apartment, agreeing to pay about thirty dollars a month in rent.
Jones becomes sexually obsessed with Lutie; recalling his youth in the Navy, Jones remembers his feelings of loneliness and sexual frustration while aboard ship, a condition that worsened as he began working and living in basement apartments and boiler rooms. Jones resents his live-in girlfriend, Min, due to her lack of physical attractiveness, venting his aggressions on her. Jones befriends Bub in hopes of getting Lutie to pay attention to him. Sensing Jones' intentions, Mrs. Hedges, the madame of a brothel, tells Jones not to bother as a wealthy white man has already taken an interest in her.
Mrs. Hedges, a heavy-set woman who is bald and badly disfigured from a fire, is referring to Junto, the proprietor of a local bar as well as the owner of several pieces of real estate. Junto has been friends with Mrs. Hedges for many years, striking up her acquaintance as she rummaged through the trash for food. Junto, who, at that time collected cans and scraps for a living, employs her then makes her a partner of sorts, putting her in charge of maintenance and rent collection once he buys his first building. After surviving the fire, Mrs. Hedges starts running a brothel out of her apartment. Acutely sensing the desperation and boredom of the young people who live in the neighborhood, Mrs. Hedges suggests that Junto open up dance halls, bars, and brothels, which Junto does. Junto, who has developed feelings for Mrs. Hedges by this point, makes an overture to her but is rejected.
Min, meanwhile, increasingly fearful of Jones, seeks out a practitioner of hoodoo. After getting a referral from Mrs. Hedges, Min finds David The Prophet. Surprised and comforted by how closely David listens to her, Min pays for a cross, some powder, some drops for Jones' morning coffee, and some candles to burn at night. Feeling reassured, Min hangs the cross over the bed as David suggested. When Min defiantly refuses to tell Jones where she had been, he advances on her angrily until he sees the cross over the bed. Feeling a superstitious dread, Jones retreats.
One night, Lutie has drinks at Junto's. After entertaining the crowd with a song, Lutie makes the acquaintance of Boots Smith, a bandleader and an employee of Junto's. Insincerely promising to help her establish a singing career, Boots convinces Lutie to take a ride with him. Lutie, who has already decided not to sleep with Boots, agrees to sing with his band. After returning home, she discovers that Bub has let Jones into the apartment while she was out and that Jones had rifled through her things.
Sometime after Lutie begins singing, Jones attacks her in the hallway, attempting to drag her into the basement. Lutie screams for help and Mrs. Hedges comes to her rescue. After inviting her inside for tea, Mrs. Hedges tells her of Junto's interest in her. Junto also tells Boots the same thing, making him promise not to pursue a romance with Lutie. Boots, indebted to Junto for helping him evade the draft, reluctantly agrees. He also agrees not to pay Lutie for her singing and to arrange a meeting between Lutie and Junto.
After Mrs. Hedges tells him yet again that he can't have Lutie, Jones angrily decides to get even with her. He convinces Bub to steal mail, paying Bub a few dollars. Bub, who initially refused Jones' offer, is eager to work; after hearing Lutie (who has just realized that she won't be paid for her singing) loudly cursing their poverty, Bub decides to help out by getting a job. Jones also implicates Min in the scheme by tricking her into getting copies of the mailbox keys made for him.
Bub is caught stealing the mail and sent to the Children's Shelter until he can be seen in Children's Court. Desperate to get Bub out of custody, Lutie consults a lawyer. Not knowing that she doesn't need a lawyer for the upcoming hearing, she agrees to pay two hundred dollars for the man's services.
Despairing of coming up with the money on her own, Lutie decides to ask Boots for help. Boots promises to get the money for her the next night. The next day, Lutie visits Bub at the Children's Shelter but is unable to ask him about the letters. That night, Mrs. Hedges once again reminds her that Junto is interested in her. Feeling apprehensive, Lutie makes her appointment with Boots. Junto is there. Realizing Boots, Mrs. Hedges, and Junto have been working in concert, she yells at Boots to get Junto out of the apartment. After conferring with Boots, Junto leaves, warning Boots once again not to make any romantic overtures to Lutie. It is then that Boots decides to take Lutie for himself whether Junto approves or not.
After a half-hearted attempt to convince Lutie to become Junto's mistress, Boots makes a sexual advance on her, kissing her and grabbing her breast. He slaps her twice when she pulls away. Lutie grabs a heavy candlestick and beats Boots to death with it. Lutie steals Boots' wallet, deciding to use the money inside to pay the lawyer's fees. Realizing that she would be caught, however, Lutie puts half the money back and flees the apartment. Knowing that she will never be able to rescue her son, Lutie buys a one-way ticket to Chicago and boards a train.