Long-chain fatty aldehydes are reported for the first time as fungal products. They were isolated from potato dextrose agar cultures ofCercospora arachidicolaas mixtures that were found by analytical procedures to consist predominantly of penta-and heptadecanal and heptadec-8-enal. Small to trace amounts of tetra-, hexa-, and nonadecanal, tetra- and pentadec-2-, and pentadec-6-enal, and heptadec-8,11 -dienal were also present, together with a mono- and a di-unsaturated C16aldehyde. Brassicasterol was also isolated.