Abstract: Effect of straw mulching on soil,tea quality and yield of young tea plantations in hilly subtropical regions was studied. Results show that straw mulching improves soil physical properties and fertility,enhances growth of earthworms and increases soil moisture in the critical 0～20cm zone of the soil profile during the critical tea growth period from April to June. At the same time, straw mulching has dynamic effects as raising soil temperature during cold periods and lowering soil temperature during hot periods. Moreover, mulching stabilizes soil temperature within a given siol layer and effectively shortens high soil temperature and desiccation spells.Most importantly,straw mulching improves tea quality and increases tea yield.Tea yield is 39.04g/m² higher under straw mulching.