Abstract: Allelopathic effects of Sonneratia apetala on the germination and seedling growth of 4 native mangrove species were investigated in a greenhouse cultivation with five concentrations (i.e. 0.1,0.2,0.3,0.4,0.5 g·mL-1) of aqueous extracts from different organs of S.apetala. Results showed that (1) S.apetala had greater allelopathic effects on germination than on seedling growth of 4 test native mangroves;(2) all concentrations except the lowest significantly inhibited the germination of native mangroves, and the inhibitory effects increased with the increasing of concentration;(3) at high concentrations of aqueous extracts,seedling growth was significantly inhibited, and the inhibitory effects decreased with the decreasing of concentration, while seedling growth was stimulated at low concentrations;(4) the order of inhibitory effects of different organs of S.apetala was: fruitrootdeciduous leaves,while the inhibitory effects of S.apetala varied with differcnt receptor species.