Picnic was very popular with theatre critics when it debuted in 1953, with special notice given to the theme of ordinary people living ordinary lives in small town America. Brooks Atkinson, writing for the New York Times, observed that "Inge has made a rich and fundamental play" from these "commonplace people." Atkinson found the female characters particularly well drawn and praised the way that Hal effortlessly brings all the women to life. Calling Picnic an "original, honest play with an awareness of people," Atkinson, also noted that while most of the characters may not demonstrate an awareness of what they are doing, "Mr. Inge does, for he is an artist."

In a review for New York Journal American, John McClain stated that Inge's characters "are easily recognizable from anybody's youth, and if the author has not chosen to bring them to grips with any problems of cosmic...