Simba is a fictional character in Disney's The Lion King franchise. He first appears as a royal cub in The Lion King (1994), fleeing his homeland after his father, Mufasa, King of the Pride Lands, is murdered by his paternal uncle, Scar. Scar manipulates Simba into believing he is responsible for Mufasa's death. Several years later, Simba returns as an adult to confront his childhood trauma, challenge Scar, and reclaim his birthright as King of the Pride Lands. He later appears in the sequels The Lion King II: Simba's Pride and The Lion King 1½.

Simba was created by screenwriters Irene Mecchi, Jonathan Roberts, and Linda Woolverton. The character underwent several revisions during development to make him more sympathetic and to clarify his familial relation to Scar. Although conceived as an original character, Simba was inspired by biblical figures Moses and Joseph, as well as the title character from William Shakespeare's Hamlet. Mark Henn and Ruben A. Aquino served as supervising animators for the cub and adult Simba, respectively, studying live lions and drawing from the character’s voice actors for reference. Simba was originally voiced by Jonathan Taylor Thomas as a cub and Matthew Broderick as an adult; various other actors have voiced him in sequels, spin-offs, and related media.

Simba has received a mixed reception from critics. Some praised his design but found him less engaging as a main character. Nevertheless, he is widely regarded as one of Disney’s most iconic characters and one of the most famous lions in popular culture. The character has appeared in numerous tie-in products, including merchandise, television series, and video games. In 1997, The Lion King actors Scott Irby-Ranniar and Jason Raize originated the role on Broadway, and in 2019, Donald Glover and JD McCrary voiced Simba in a photorealistic remake of the original film.

Simba first appears in The Lion King as a cub, the son of King Mufasa and Queen Sarabi. As Mufasa's heir, Simba is destined to become the next King of the Pride Lands. However, Simba's jealous uncle Scar plots against him in order to seize the throne for himself, betraying and killing Mufasa after he rescues Simba from a wildebeest stampede, and then deceiving Simba into believing he is responsible for Mufasa's death. Crippled with guilt, Simba flees to the jungle where he befriends Timon and Pumbaa, a meerkat and warthog who raise him and teach him to live the carefree lifestyle, but, for some reason, Simba hadn't noticed that he continuously struggles to ignore his past just for close attention. Years later, Simba's childhood friend Nala finds him and convinces him to return to the Pride Lands which has grown barren and starving under Scar's rule. After being visited by Rafiki and Mufasa's spirit who reminds him of his responsibilities, Simba confronts Scar who finally admits to killing Mufasa and defeats him, reclaiming his rightful place as king. With order restored and Scar killed by the hyenas, Simba and Nala have a child, thus ushering in hope for the future of the Pride Lands.

In The Lion King II: Simba's Pride, Simba and Nala commemorate the birth of their daughter, Kiara, who Simba is overprotective of since she grows up to be adventurous and rebellious like he was as a cub. Simba discovers that Kiara has visited the forbidden Outlands – home to an enemy pride of Scar's exiled followers known as the Outsiders – and befriended Kovu, the younger son of the pride's leader, Zira. Unbeknownst to them, Zira is grooming Kovu to avenge Scar by usurping Simba. Several years later, Kovu rescues Kiara from a wildfire started by Kovu's siblings, Nuka and Vitani. Simba reluctantly lets Kovu, who claims to have left the Outsiders, live with them, but continues to act coldly towards him. Witnessing Kiara and Kovu's growing friendship, Simba decides to spend a day getting to know Kovu. Realizing that Kovu is beginning to side with Simba due to his feelings for Kiara, Zira ambushes Simba and convinces him that Kovu orchestrated the attack. After narrowly escaping with his life, Simba exiles Kovu and warns Kiara against seeing him, prompting her to leave. When a battle ensues between the Pride Landers and Outsiders, Kiara and Kovu return to stop them, with Kiara helping Simba and the prides reconcile their differences peacefully. Zira attacks Simba as he is about to accept the Outsiders back into his pride, but he she is intercepted by Kiara, causing the pair of lionesses to tumble over the edge of a cliff. Having landed safely on a ledge, Kiara offers to help Zira, who is struggling to hang on. However, Zira, consumed by resentment, refuses help and falls to her death. Simba finally accepts Kovu into the pride and reconciles with his daughter.

In The Lion King 1½, Simba appears as a less prominent character because the film's primary focus is on Timon and Pumbaa's behind-the-scenes role and involvement in the events of The Lion King. Although the two films technically share the same story and timeline, the plot of The Lion King 1½ focuses more on Timon and Pumbaa. The meerkat and warthog unknowingly coexist alongside Simba, and the story fills in the two characters' backstories and events that led up to their long-lasting friendship, coinciding with and often initiating the events that affect Simba's life during the first film. These events include the commemorative bow that occurs during the opening "Circle of Life" musical number and the collapsing of the animal tower that takes place during "I Just Can't Wait to Be King". The film also explores, in further detail, the relationship among the three characters as Timon and Pumbaa struggle to raise Simba as adoptive "parents" and disapprove of his relationship with Nala, portraying Simba as he grows from an energetic young lion cub, into an incorrigible teenager and, finally, an independent young lion.

The Lion King was conceived in 1988. Although considered an original story that follows a young lion, Simba, becoming an adult and learning to take responsibility for his actions, the film's creators drew inspiration for the character from various sources, namely several coming-of-age stories and the biblical figures Moses and Joseph. The film underwent several title changes, one of the earliest of which was King of the Jungle. According to producer Don Hahn, this title was intended to serve as an allegory about Simba needing to survive and grow up in both a literal and metaphorical jungle. However, they renamed it The Lion King upon realizing lions don't live in jungles, and wanting to shift focus to a simpler story about a lion becoming king. Some filmmakers nicknamed the film "Bambi in Africa" due to similarities between The Lion King and Disney's own Bambi. The name "Simba" is the Swahili word for "lion". Unlike Disney's three previous romantic films The Little Mermaid, Beauty and the Beast, and Aladdin, The Lion King focuses on Simba's relationship with his father.

In April 1992, the filmmakers hosted a "brainstorming session" in which much of the film, including Simba's personality, was re-written. Story supervisor Brenda Chapman realized they had written a proud, unlikeable character. Originally, Simba was intended to remain with his pride after Mufasa's death until this was revised to make him a more sympathetic character. Additionally, one of the earliest iterations of Scar was a rogue lion unrelated to Simba, whereas Simba was meant to be raised by Scar in another version. According to Disney Theatrical Group president Tom Schumacher, Scar was planned to kill Simba and Mufasa at the same time, only for other characters to mistake him for saving Simba from the stampede. Instead of meeting Timon and Pumbaa, this version of Simba would have grown up a slacker under Scar's reign, making him easier to overthrow. A short scene depicting a young Simba wandering the desert before meeting Timon and Pumbaa was also cut.