The film received positive reviews from critics. As of December 2019 Rotten Tomatoes reported 32 out 35 reviews were positive, giving the film an approval rating of 91%. The website summarized the critics consensus by saying, "In addition to offering an enlightening early look into the world of future star/politician Arnold Schwarzenegger, "Pumping Iron" provides a witty and insightful overview of competitive bodybuilding." On Metacritic the film has a score of 72% based on reviews from 12 critics, indicating "generally favorable reviews".