Megan "Meg" Griffin is the sweet-natured teen-aged daughter of the title character Peter Griffin in the fiction world of the animated TV series Family Guy. Her voice was provided by Lacey Chabert for the first season and by Mila Kunis for the last two seasons.

Meg's most notable character trait is her burning desire for popularity. The fact that she is not well-accepted in her school often leads to a lot of crying and melodrama from her.

Meg is seen by fans as the least interesting family member. This is clearly intentional with many jokes being at her expense. In the episode "The Thin White Line", the Griffin family is commissioned by Brian's psychiatrist to write reasons why the pet should attend rehab. When Meg is asked to start, the psychiatrist quickly interrupts and asks someone else of more interest to take over. Other characters on the show freely disrespect her, including the weight guesser, who guesses how much she weighs ("a lot"), and Peter, who forgets that Meg is a member of the family and instead puts Boba Fett in her place.

She also often feels embarrassed by her family. In the episode "Fifteen Minutes Of Shame" she got her family on local newscaster Diane Simmons's talk show to confront them. The family's appearance on that show led to a reality show, The Griffins. However, this simply increased Meg's feelings of embarrassment, leading her to quit the show. She was replaced by a tall, very attractive, blonde girl who quickly began to steal the spotlight. The Griffins eventually protested, were replaced by a celebrity cast, and then reunited with Meg.

Neil Goldman, a nerdy kid at Meg's school, wants to be romantically involved with her in many episodes – Meg does not. In the episode "The Kiss Seen Round the World", the two of them kiss each other when faced by their deaths since Meg wanted to kiss a boy before she died. Neil uses video footage of the kiss, along with numerous printed shirts given away for free at school, to show everyone his version of events – that more was going on than there actually was. Meg eventually proves to everyone that her feelings for Neil are far from love. It is also revealed in this episode that Meg is allergic to peanuts.

In one episode, Brian hints at Meg's real father not being Peter Griffin, but rather one Stan Thompson. Meg, however, is too busy listening to her headphones to notice he said anything.