Marc Daniels (January 27, 1912-April 23, 1989) was an American television director, born Danny Marcus in Pittsburgh, Pennsylvania in 1912. After working in stage productions and serving in World War II, Daniels was hired by CBS Television to direct for its first dramatic anthology program, Ford Theater. He mastered live television directing, and then directed the first 38 episodes of I Love Lucy, helping to establish many of the techniques used in (filmed) situation comedy directing.

Daniels spent nearly 40 years directing television, including series such as Gunsmoke, Fame, Alice, and Hogan's Heroes.

To science fiction fans, Daniels is best known for directing over a dozen episodes of Star Trek: The Original Series (including the classic "Mirror, Mirror") and writing an episode of the animated series ("One of Our Planets is Missing").

His last television work was on Lucille Ball's last series, Life with Lucy. He died of congestive heart failure in 1989 in Santa Monica, California.

Is portrayed by Doug Franklin in Lucy & Desi: Before the Laughter (1991) (TV).

Is credited for suggesting actress Vivian Vance for the role of Ethel Mertz to Desi Arnaz and producer Jess Oppenheimer (I).