* Richard Egan as Dr. Ken Anderson
* Dorothy McGuire as Sylvia Hunter
* Troy Donahue as Arthur Hunter
* Sandra Dee as Molly Stratton
* Constance Ford as Helen Tyler
* Arthur Kennedy as Roy Stratton
* Betty Field as Mrs. Stratton
* Mort Sahl as Professor Thornton
* Robert Horton as Ted Carpenter
There were also a few smaller roles played by actors including :
* Barbara Eden as Irene Agosti
* Chad Everett as Bart
* David Janssen as George Hunter
* Lita Milan as Mrs. Agosti
It's worth noting that "A Summer Place" became a huge hit and helped launch the careers of Troy Donahue and Sandra Dee, making them teen idols of the era.