Thommy Berggren (born Tommy William Berggren; 12 August 1937) is a Swedish actor. He was a frequent collaborator of director Bo Widerberg, and was primarily active between the early 1960s and mid-2000s.

Tommy William Berggren was born on 12 August 1937, in Mölndal, Sweden, an impoverished working class district on the country's west coast. His father, William Berggren, was a sailor by trade and a socialist involved with the worker's rights movement in Sweden. His mother was employed at the local factory and was similarly politically inclined. When he was born, he suffered with a disease of the lungs, which caused him to have to stay in a hospital facility for one year.

Berggren's father was also an alcoholic. In Stefan Jarl's 2002 film The Bricklayer, a documentary about Berggren's life and career, he recounted an incident in which he had walked a great distance to meet his father at a train station, only to discover that he had not kept the appointment with his son. Instead, he had remained in town drinking. Berggren later defended his father, stating that he was not aggressive or abusive in any way, and that both of his parents were well-meaning people.

Berggren's father supported and encouraged his son's career choice as an actor. Believing that acting and the theatre were "immaterial", he encouraged his son to be "a better actor than the rest".

Berggren began to study acting at the Pickwick Club Theatre School in Gothenburg. He made his stage debut at the age of seventeen at the Atelier Theatre [sv]. He worked there for two years, until he was accepted into Gothenburg City Theatre's drama course in 1956.

In 1959, he was engaged as a regular player at the Gothenburg City Theatre, where he worked until 1961, when he was granted a position with the Royal Dramatic Theatre in Stockholm. In his first role there, he portrayed Nick in Ingmar Bergman's production of Edward Albee's play Who's Afraid of Virginia Woolf?. In 1993, he made his debut as a director at the Royal Dramatic Theatre with Harold Pinter's The Homecoming. He later directed plays at the Stockholm City Theatre, including August Strindberg's Miss Julie and Samuel Beckett's Waiting for Godot.

In 1961, Berggren made his film debut in Pärlemor. The next year, he met aspiring director Bo Widerberg, who became his good friend and one of his most frequent collaborators. Like Berggren, Widerberg strongly believed that films needed to focus on human relationships, have a greater political significance, and be socially conscious. As early as 1960, Berggren declared in an interview that he only wanted to do films that he could truly stand for, to play people who developed – an attitude he has maintained through the years.

Berggren and Widerberg's first feature together was Barnvagnen, about a woman who chooses single parenthood instead of marriage. The two continued their partnership with 1963's Raven's End, a portrait of working class life in 1930's Sweden. Berggren portrayed Anders, a young aspiring writer who finds his hopes and dreams dashed upon the reality of an impoverished existence. In 1966, Berggren was awarded the Guldbagge, the Swedish equivalent of the Oscar, for Widerberg's Heja Roland!. The following year, Berggren starred in Elvira Madigan, Widerberg's first movie to have commercial success internationally.