The invention provides a seedling propagation and cultivation method for a mangrove plant, heritiera littoralis. The seedling propagation and cultivation method comprises the following steps: step A, selecting plants of 5-20 year heritiera littoralis having no plant diseases and insect pests as mother trees, collecting fruits with plump forms and blue-dun peelings from August to October per year, disinfecting, sun drying and bagging; step B, storing the fruits into sand; step C, selecting a nursery field, disinfecting seedbed substrate, and 10 to 15 days later, carrying out direct sowing to the fruits of heritiera littoralis; step D, carrying out acclimatization to the seedlings of heritiera littoralis so as to adapt to halophytic environment and fresh water environment; step E, after the seedlings of heritiera littoralis grow to 0.8 to 1.5m, carrying out earth removing and transplanting and then placing the seedlings into bottoms of planting holes waiting for planting, and using seaside natural marine mud for strong seedlings. The seedling propagation and cultivation method provided by the invention expands the survival adaptation range of the seedlings of the heritiera littoralis, the seedlings cultivated not only can be planted in a intertidal zone environment where sea water can reach directly, but also can be cultivated in land far away from sea water, so that forestation and propagation of the heritiera littoralis are facilitated, and the seedling propagation and cultivation method is suitable for protection and production to heritiera littoralis resource, and is also is suitable for landscape application.