Marlena Evans is a fictional character on the NBC/Peacock soap opera Days of Our Lives, a long-running serial about working life in the fictional town of Salem. She has been played by actress Deidre Hall since 1976, but the character was absent from the show from 1987 to August 1991 and again from January 2009 to September 2011. Marlena was created by scriptwriter Pat Falken Smith and executive producer Betty Corday, and has become one of Days of our Lives' most well-known characters. Hall made her debut on the soap on June 21, 1976, currently making her the second longest running actress on the serial, surpassed only by Suzanne Rogers.

Days of Our Lives is an American television soap opera that aired on the network NBC from 1965 to 2022 and currently streams new episodes on Peacock. The soap is one of the longest-running scripted television programs in the world, airing nearly every weekday since November 8, 1965. A co-production of Corday Productions and Sony Pictures Television, the series was created by husband-and-wife team Ted Corday and Betty Corday. During Days of Our Lives' early years, Irna Phillips served as a story editor for the program and many of the show's earliest storylines were written by William J. Bell, who would depart the series in 1975 to focus full-time on The Young and the Restless, which he created for CBS in 1973. Following the 2007 cancellation of Passions, Days of Our Lives remained the only soap opera airing on NBC. On August 3, 2022, NBCUniversal announced that it would relocate the series exclusively to its Peacock streaming service beginning September 12 after 57 years on the network and leaving NBC as the only Big Three network without a daytime serial.