A raven-haired, sometimes blonde (particularly in the earlier years) pretty actress, Dilys Laye was capable of a wide range of roles, from straight drama to comedy. She began in the 1950s, like most other British screen actresses of the era, in studio-system-style films. One of her first films was Paper Gallows (1950) and she continued in popular movies like Blue Murder at St. Trinian's (1957) and Doctor at Large (1957).

Today she is often remembered for her appearances in the "Carry On.." films. Her first "Carry On..." appearance was in Carry on Cruising (1962), where along with Esma Cannon she stole many of the best comedy scenes from the regular cast; the bar scene is an example of this. She took over the role at four days' notice when Joan Sims was unable to appear because of ill health. Her next 'Carry On...' appearance saw her take on a sinister and darker role in Carry on Spying (1964) as Lila. She even sang, in a café-bar scene. In Carry on Doctor (1967) she played patient Mavis Winkle, who is searching for love and finds it in the unusual place of the hospital ward, and in Carry on Camping (1969) she appeared alongside "Carry On..." legend Joan Sims. They were perfectly cast together and complement each other's performances throughout the movie.

After that time her work was mainly on the stage with some television and film appearances. She made appearances in soaps such as Coronation Street (1960) and EastEnders (1985). Other character parts included Holby City (1999) and Doctors (2000).

She played Queen Elizabeth II in The Amazing Mrs Pritchard (2006).