Fifteen lignite samples from the province of Yunnan were analysed by organic petrography and geochemistry. Twelve of the samples represent the very pale (yellow) Baipao coal, the other three were normal coals of a medium brown colour. The Baipao coal consists mainly of mineral-bituminous groundmass, whereas the normal coal is characterised by well-preserved tissues derived from gymnosperm wood. Up to 190 mg/g C(org) of extract is extractable from the Baipao coal; only 63 mg/g C(org) from the normal coal. The n-alkane fraction of the Baipao coal extract consists of high amounts of hopanes and shows the predominance of nor-abietane within the diterpenoids present. The first group of compounds points to intensive bacterial activity, while the second compound indicates not only that gymnosperms are present but also that a relatively oxygen-rich environment existed at the time of deposition. From the petrographic and organic geochemical characteristics it is concluded that the Baipao coal was formed from the same plant source material as the normal coal, but underwent stronger decay.