The contamination was found in a single bottle of Johnson's baby powder purchased from an online retailer, prompting the lot, or around 33,000 bottles, to be recalled, the company said.
The amount of asbestos found was considered a "sub-trace level" (no greater than 0.00002%), but the company issued the recall "out of an abundance of caution."
Johnson & Johnson says it is working with the Food and Drug Administration to investigate how the bottle became contaminated.
Two previous tests, one as recently as last month, found no asbestos, the company said.
Exposure to asbestos can cause mesothelioma, a rare but fatal cancer that targets the lining of the lungs.
Anyone who purchased a bottle of Johnson's Baby Powder Lot #22318RB is advised to not use the product.
For refund information, contact the Johnson & Johnson Consumer Care Center online or by calling (866) 565-2229.