Célestine Ann "Tina" Beyoncé Knowles (née Beyoncé, born January 4, 1954) is an American businesswoman, fashion designer, author, and philanthropist known for establishing the brands House of Deréon and Miss Tina by Tina Knowles. She is the mother of singers Beyoncé and Solange Knowles and was married until 2011 to their father Mathew Knowles, the manager of Destiny's Child. For her contribution to the fashion business, Knowles was honored at the Accessories Council Excellence Awards in 2001.

Célestine Ann Beyoncé was born in Galveston, Texas, the youngest of seven siblings. Her mother, Agnéz Beyincé (née Deréon) (1909–1980), was a seamstress. Her father, Lumis Albert Beyincé (1910–1982), was a longshoreman. Due to a clerical error on her birth certificate, her surname (Beyoncé) is spelled "one letter different" from that of other members of her family. She is of Louisiana Creole heritage. Knowles was raised Catholic and attended Catholic school. Her family's roots are from Boutte, Louisiana. She is a descendant of Acadian leader Joseph Broussard and French military officer Jean-Vincent d'Abbadie de Saint-Castin. While in high school, Knowles was a part of a singing group called the Veltones, inspired by the Supremes.

On January 5, 1980, she married Mathew Knowles, a Xerox salesman who would later quit his job to manage Destiny's Child. The pair divorced in November 2011, and share two children: Beyoncé (born 1981) and Solange (born 1986).

In the summer of 2013, she started dating actor Richard Lawson. Prior to dating, Knowles had been friends with Lawson for more than 30 years. They initially met through her friendship with his late sister. In a 2018 interview, Lawson stated that he had "always admired her from afar and up close too." The couple were married in Newport Beach, California, on April 12, 2015. Knowles filed for divorce from Lawson in July 2023, citing irreconcilable differences, and it was finalized in 2024.

Through her marriage with Lawson, Knowles became a stepmother to his daughter Bianca Lawson and his son Ricky. She also often refers to Destiny's Child member Kelly Rowland as her daughter, whom she helped raise from the age of 11 when Rowland began living with the Knowles family. In an open letter published by Time magazine in 2015, Knowles stated "I gave birth to two of you, but I have four incredible daughters" referring to Beyoncé, Solange, Kelly Rowland, and her niece Angie Beyincé.

Knowles has four grandchildren, including Blue Ivy Carter. In addition to her grandchildren through daughters Beyoncé and Solange, she also considers herself a grandmother to Kelly's two children.

In late 2024, Knowles was successfully treated for stage 1 breast cancer.

As a fashion designer, Knowles has been featured in publications such as Vogue, Cosmopolitan, Harper’s Bazaar, L'Officiel, InStyle, and Sports Illustrated. She has also designed costumes for a number of films including Dreamgirls, Pink Panther, Austin Powers in Goldmember, Obsessed, and Cadillac Records.