There's tremendous pressure on employees dealing with Apple's new products to maintain secrecy over the gadgets.
The 25-year-old man worked in product communications at Foxconn Technology Group, a Taiwanese firm that makes many Apple products.
Although Apple and Foxconn have confirmed the suicide, they haven't provided details about the circumstances.
A newspaper says the worker was responsible for sending iPhone prototypes to Apple, and on July 13 he reported that he was missing one of the 16 fourth-generation units in his possession. The paper quotes his friends as saying security guards searched his apartment, detained him and beat him, and that he later jumped from the 12th floor of his apartment building.
Apple says it's "saddened by the tragic loss" and that its suppliers are required to treat workers with dignity and respect.