Abstract: For screening plant extracts with high bioactivity to Alternaria alternata, 12 kinds of extracts from 10 plant species were tested on the spore germination of Alternarial alternata indoors and the control effects in field plot.The results showed that the extracts from fruits of Litsea cubeba by water steam, seeds of Arctium lappa by petroleum ether and flowers of Syzygium aromaticum by water steam could obviously inhibit the germination of Alternarial alternata spore and had good control effects in filed also.