Thelma Holt CBE (born 4 January 1932) is a British West End producer and former actress. She is described as "one of the most influential" producers in the UK industry, and has been honored with both an Order of the British Empire (UK) and an Order of the Rising Sun (Japan, 2004).

In 2018, she received the Sam Wanamaker Award from Shakespeare's Globe to celebrate work "which has increased the understanding and enjoyment of Shakespeare." She was known as a close collaborator and champion of Japanese director Yukio Ninagawa from 1987 until his death in 2016.

Holt was born in Barton-on-Irwell, Lancashire, to English electrical engineer Peter David Holt and Irish-born Eleanor Finnagh Doyle. She grew up Catholic. Her father was killed in an air raid during World War II, leaving her mother to raise her and her older sister Elizabeth. After attending St Anne's School for Girls, she trained at the Royal Academy of Dramatic Art (RADA) from 1952 to 1954.

Graduating from RADA, Holt enjoyed a fairly successful career as an actress and understudied her friend Vanessa Redgrave. She then founded the Open Space Theatre on Tottenham Court Road in partnership with Charles Marowitz, a theatre which quickly became the forerunner of the London Fringe. In 1977, she joined The Round House in Chalk Farm as Artistic and executive director, instigating a policy of bringing the best of regional theatre to London including the Citizens Theatre (Glasgow), Royal Exchange Theatre Company (Manchester), and Stephen Joseph Theatre Company (Scarborough).

From 1977 to 1983, Holt was artistic director at the Roundhouse. In 1983, The Roundhouse closed and Thelma Holt joined the Theatre of Comedy as executive producer, where she produced Loot by Joe Orton, directed by Jonathan Lynn and starring Leonard Rossiter. She is also an Associate Producer at the Royal Shakespeare Company and a patron of the Oxford University Dramatic Society (OUDS).

In 1985, Holt joined the National Theatre as head of Touring and Commercial Exploitation. She was responsible for the following NT West End transfers: A Chorus of Disapproval, The Petition, Brighton Beach Memoirs, Three Men on a Horse and A View from the Bridge. She also oversaw major tours of National Theatre productions abroad, with performances in Paris, Vienna, Zurich, North America, Moscow, Tbilisi, Tokyo, and Epidavros.

Holt produced International 87, a series of four visits to the National Theatre by international theatre companies: The Hairy Ape directed by Peter Stein for the Schaubühne; Miss Julie and Hamlet directed by Ingmar Bergman for the Royal Dramatic Theatre, Stockholm; Macbeth and Medea directed by Yukio Ninagawa for the Ninagawa Theatre Company, and Tomorrow was War by the Mayakovsky Theatre Company from Moscow. Holt received the Olivier/Observer Award for Outstanding Achievement in the Theatre as well as an award from Drama Magazine. In 1998, she co-produced an adaptation of The Fairy-Queen directed by Adrian Noble for the Aix-en-Provence Festival.

She then produced International 89, this time festuring Tango Varsoviano by Teatro del Sur (Buenos Aires), Grapes of Wrath by the Steppenwolf Theatre Company (Chicago), Uncle Vanya from the Moscow Art Theatre and Suicide for Love by the Ninagawa Theatre Company.