A revised structure of colossolactone G (1), seven new triterpene lactones, ganodermalactones A-G (2-8), and five known triterpene lactones, colossolactone I (9), schisanlactone B (10), colossolactone B (11), colossolactone E (12), and colossolactone IV (13), and ergosterol have been isolated from cultured biomass of the macrofungi Ganoderma sp. KM01. Their structures were identified by spectroscopic methods. Structures and relative configurations of 3, 7, and 8 were confirmed by X-ray crystallographic analysis. Compounds 7, 10, and 12 exhibited antimalarial activity against Plasmodium falciparum in the range 6.0-10.0 μM (IC50).