A saprotroph (or saprobe) is an organism that obtains its nutrients from non-living organic matter, usually dead and decaying plant or animal matter, by absorbing soluble organic compounds.

Since saprotrophs cannot make food for themselves, they are considered a type of heterotroph. They include many fungi (the rest being parasitic, commensal or mutualistic symbionts), bacteria, and protozoa. Animal scavengers, such as dung beetles, vultures, and a few unusual non-photosynthetic plants are also sometimes referred to as saprotrophs, but are more commonly called detritivores.