Cannibalism (also called product or market cannibalism) occurs when a product released by a company competes for market share with an existing product of theirs. The new product "eats" demand for the old, reducing sales and profit of their existing product. Some amount of product cannibalism is expected with new product launches, and companies normally consider the financial risks and rewards of releasing new products carefully.

Cannibalism can result in overall positive or negative effects on a company's bottom line, and can be either intentional or unintentional. When it's intentional, it's referred to as a cannibalisation strategy.‍