Sonequa Chaunté Martin-Green (/səˈniːkwə/; née Martin; born March 21, 1985) is an American actress. She is best known for her television roles as Michael Burnham, the main character in the streaming television series Star Trek: Discovery, and as Sasha Williams on The Walking Dead. Before that, Martin-Green starred in several independent films before gaining her first recurring role, as Courtney Wells on The Good Wife. Later, she had recurring roles as Tamara in Once Upon a Time and Rhonda in New Girl.

Sonequa Martin was born and raised in Russellville, Alabama. Her parents were Charles Winston Martin (1943–2021) and Vera Lynn Martin-Moore (née Freeman; 1950–2021). Her parents divorced and her mother remarried. In April of 2021, her parents died one day apart. Her father died after a short cancer battle. Her mother, a three-time cancer survivor, died of a heart attack the next day.

Martin-Green has one full sister, NaKisha, and three older paternal half-sisters.

Martin-Green initially planned to become a psychologist before deciding in the tenth grade to pursue a career in acting. On her decision to become an actor, she said, "I didn't know I was going to be an actor until I was 16. I thought I was going to be a psychologist, which is interesting because it's very similar to acting. I was fascinated with human behavior and why people do what they do. I was in the middle of rehearsal in 10th grade when I had this epiphany. And so I got my theatre degree from the University of Alabama."

Martin-Green graduated from the University of Alabama in 2007 with a degree in theatre.

While known primarily for her television roles, Sonequa Martin-Green made her film debut in 2009. In 2009, she played the lead role of Tosha Spinner in Toe to Toe opposite Louisa Krause, the fiercely determined scholarship student who seeks to build a brighter future outside of Anacostia and away from one of Washington's poorest neighborhoods. The film focuses on her friendship and rivalry with Jessie (Louisa Krause), a privileged girl from Bethesda whose promiscuous tendencies threaten to become her undoing. They both strive to gain a better understanding of one another's plight as society threatens to drive them ever farther apart. The film received generally positive reviews, with Martin-Green's performance receiving critical acclaim, even from the film's detractors. In November 2018, it was announced Martin-Green would star in The Outside Story, opposite Brian Tyree Henry, directed by Casimir Nozkowski. In July 2021, she played the role of Kamiyah James in Space Jam: A New Legacy.

Martin-Green has had various guest and recurring roles in TV shows. She made her television debut in 2008, appearing on NBC's Law & Order: Criminal Intent as Kiana Richmond. She then gained her first recurring role on Army Wives as Kanessa Jones the following year. In 2009, she received the role of Courtney Wells on The Good Wife, her first recurring role playing an adult character as opposed to playing a teenager with her previous roles in both film and television. She appeared on the show for two years before making two more appearances in Gossip Girl and NYC 22 in 2011.

In 2012, she was cast in a recurring role on The Walking Dead as Sasha, the sister of Tyreese (Chad Coleman), an original character, exclusive to the television series. Martin-Green auditioned for the role of Michonne albeit with a pseudonym due to the secrecy of the auditioning process. When Danai Gurira, who Martin-Green said was "the perfect choice", was cast, former showrunner Glen Mazzara still wanted Martin-Green to be a part of the show and decided to create a role specifically for her instead. Martin-Green explained: "[Sasha] was supposed to be a recurring character and as we kept going forward, they picked up my option to be a regular. It's very rare and I'm still quite dumbfounded about it but Glen and I hit it off and I still appreciate him. He wanted to work with me and wrote Sasha for me". She was promoted to a series regular for season 4 with Emily Kinney and Coleman.