The titular character of the novel, White Fang undergoes a variety of transformations that underscore each of the novel's main themes. White Fang starts out life as a strong, curious pup that quickly rises as the "fittest" in the pack. Through hunting lessons from his mother and various other teachings from his three masters, White Fang learns how to adapt to any situation, fight for his life, and emerge from any fight as the victor. The consequence of being a superior beast is that White Fang is isolated, abused, and depressed. Through domestication with Weedon Scott, however, White Fang learns to love and, for the first time, finds belonging.
Weedon Scott represents humanity's compassion, kindness, and love. A wealthy gold prospector, Weedon rescues White Fang from Beauty Smith's hideous dogfighting ring and nurses the wolf back to health, earning his respect and trust in the process. Through Weedon's love, White Fang is given a chance at redemption, which he achieves in learning to love and passing that love on to the next generation of pups. Whereas White Fang had an impersonal, businesslike relationship with Gray Beaver and a volatile, hate-filled relationship with Beauty Smith, with Weedon Scott, White Fang feels part of a family, and he uses all his learned lessons in service to his master.
Gray Beaver, an Indian fur trader, plucks White Fang from the wild and raises him to work as a sled dog. Of White Fang's three masters, Gray Beaver sits in the middle of two extremes. He provides food and shelter but beats White Fang into submission. As a result, White Fang grows to respect Gray Beaver but never to love him. White Fang escapes Gray Beaver's camp but returns out of loyalty and fear. Never a companion animal, White Fang spends much of his time under Gray Beaver's command in isolation.
Kiche represents the ability to do whatever needs to be done to survive. The reader first sees Kiche luring sled dogs away from their masters in the novel's opening chapters, baiting the dogs into the open before attacking and eating them. In a time of extreme famine, Kiche uses cunning rather than brute strength to survive. She passes her superior genes down to White Fang and teaches him how to hunt and how to pander to humans for protection. In the end, Kiche is driven by her instincts, forgetting White Fang as soon as she has a new brood of pups to care for.
Beauty Smith is a malformed monstrosity of a man, hideous both physically and in spirit. He lusts after White Fang's fighting strength when he sees White Fang stalking prospectors' dogs in the Yukon and devises to own him at any cost. When Gray Beaver refuses to sell him, Beauty Smith plies Gray Beaver with alcohol and manipulates him. From the first day, Beauty Smith uses violence to control White Fang and force him to fight, making the wolf even more vicious than before. While Beauty Smith's evil is a result of a cruel environment, just as White Fang's is, London offers no redemption for his character, suggesting he was born ill-formed.