For the estimation of the amount of biomass in solid-state fermentation, various indirect methods are available. The suitability of respiration measurements and the content of various cell components were evaluated for Coniothyrium minitans grown on different media. Protein and nucleic acid measurements are useful as indicators for total biomass when C. minitans is grown on potato dextrose agar (PDA) but not on nutrient agar with glucose (NAG) or starch (NAS) as a carbon source. None of the methods tested are reliable enough to discriminate between the amounts of mycelial and conidial biomass of C. minitans when used solely; however, using PDA as growth medium, a distinction can be made between mycelial and conidial biomass by combining the content of glucosamine, protein, and nucleic acid with each other or with spore counts.