Victor is an ambitious young scientist from a distinguished Genevan family. Driven by a thirst to understand the secrets of nature, he leaves his idyllic childhood behind to study at the university in Ingolstadt. His obsessive pursuit of creating life leads him to isolate himself from his family and the natural world.

Created from reanimated biological matter, the Creature is a massive, physically imposing being with a hideous appearance. Despite his terrifying exterior, he awakens with the innocent curiosity of a child and a natural capacity for love. Repeated violent rejections by human society force him into isolation, deeply altering his disposition.

Walton is a self-educated English explorer commanding a ship bound for the Arctic. He desires glory and the discovery of a northern passage, willing to risk extreme danger to achieve his goals. He suffers from a lack of intellectual companionship until he brings a frozen stranger aboard his ship.

Henry is the son of a Geneva merchant and Victor's closest companion. Unlike Victor's focus on science, Henry is drawn to literature, languages, and the moral relations of things. He possesses a joyful, poetic spirit that often comforts Victor during times of distress.

Elizabeth is a beautiful, gentle orphan taken in by the Frankenstein family. Raised alongside Victor, she is universally adored by the household and intended from a young age to become Victor's wife. She acts as a calming, nurturing presence within the family home.

Caroline is the daughter of a ruined merchant who is rescued from poverty by Victor's father. She becomes a devoted mother to Victor and actively seeks out opportunities to perform charitable acts, including the adoption of Elizabeth Lavenza.

Victor's father is a distinguished and affluent public servant in Geneva. He is a practical man who dismisses Victor's early interest in alchemy, preferring rational and modern science. He provides a stable, loving home for his children and wards.

William is Victor's youngest brother, a beautiful and cheerful child. He represents the innocent joy of the Frankenstein family before tragedy strikes.

Ernest is the middle Frankenstein son. He is sixteen years old when Victor is at university and possesses an active, outward-looking disposition compared to Victor's academic isolation.

Justine is a young woman who was taken in by the Frankenstein family after experiencing a difficult home life. She acts as a servant and caretaker, particularly to young William, and is treated with great affection by the family.

Margaret is Robert Walton's sister, living in England. Though she does not appear directly in the narrative, she serves as the silent audience for Walton's letters detailing his expedition and his encounter with Victor Frankenstein.

M. Krempe is a professor of natural philosophy at Ingolstadt. He is brusque and dismissive of Victor's previous self-education, sharply criticizing the ancient alchemists Victor studied and demanding he begin his studies anew.

M. Waldman is a chemistry professor whose eloquent lectures on the power of modern science captivate Victor. Unlike Krempe, Waldman is encouraging and validates the foundational work of the ancient alchemists, inspiring Victor's obsessive scientific pursuits.

De Lacey is an elderly, blind man living in exile in a poor cottage in Germany. Once an affluent Parisian, he lost his wealth and standing due to political injustice. His blindness allows him to judge individuals by their character and voice rather than their physical appearance.

Felix is De Lacey's son, a devoted young man who works tirelessly to support his impoverished family. He carries a deep sadness from his family's exile and his separation from his romantic interest, Safie.

Agatha is De Lacey's daughter. Despite living in poverty, she maintains a gentle disposition and sacrifices her own meager food rations to ensure her blind father has enough to eat.

Safie is an Arabian woman who travels across Europe to reunite with Felix. As she learns the local language alongside the cottagers, the secretly observing Creature learns to speak and read by listening to her lessons.

Safie's father is a Turkish merchant who was unjustly condemned to prison in Paris. Though Felix helps him escape, the merchant deceitfully attempts to prevent Safie from marrying Felix, leading to the ruin of the De Lacey family.

Mr. Kirwin is an Irish magistrate who oversees a local murder investigation. He questions Victor when the scientist washes ashore and becomes the prime suspect, later showing unexpected compassion during Victor's resulting illness.