AbstractFloristic inventories of six rain forest fragments on Holy Hills of Dai people in Xishuangbanna , southern Yunnan , were made. Change in floristic composition of the fragments was analyzed based on the comparison with the continuous primary rain forest of the region. With fragmentation and growing disturbances on the rain forest fragments , some plant families , such as Papilionaceae , Rutaceae and Euphorbiaceae , conspicuously increased in relative number of species or species percentage , while some families such as Ochidaceae , Lauraceae , Annonaceae and Urticaceae , decreased in relative number of species , i.e. their former dominance faded owing to the invasion of a lot of pioneers and declination or extinction of shande tolerant and climax species. In composition of geographical elements of the flora of fragments , the elements of pantropicand tropical Asia to tropical Africa distributions increased in percentage at genus level and those of wide distri- bu tion increased , while those of the usually limited or local distribution decreased at species level.