The spores of Homalothecium sericeum (Hedw.) Schimp., Brachythecium populeum (Hedw.) Schimp., B. velutinum (Hedw.) Schimp. var. salicinum (Schimp.) Mönk., B. velutinum (Hedw.) Schimp. var. validum C. Jens. and Eurhynchium hians (Hedw.) Sande Lac. were studied by light and scanning electron microscopy for the first time. The apertural region consists of a leptoma in all spores. Two spore types, characterized by their surface ornamentation, are established, reflecting the species taxonomic relationships. While the surface ornamentation is of the insuloid type in Eurhynchium hians, it consists of a granuloid type in Homalothecium sericeum, Brachythecium populeum, B. velutinum. var. salicinum, B. velutinum var. validum. The spore wall of the family Brachyteciaceae includes sclerine (the dinstinction between exine and perine may be difficult to define) and intine. The taxonomy of the genera Brachytecium and are discussed on the basis of their spore morphology.