Abstract: The ecotope, habit and morphological characters were investigated and identified on weedy rices in Hainan Island. Weedy rices appeared scattering distribution or no gregarious plants, and were allied to their companion cultivars such as cv. Ruidao (deepwater rice) in morphology, but differed from cultivars in deciduous spikelets and from high to low dormancy of seeds. The origin and utilizing value of weedy rices were discussed according to their hybridism, stomata distribution disordered i. e. middle stomata on leaves, etc.

Key words: ecological investigating, identifying, weedy rices in Hainan Island

摘要： 对海南岛杂草稻的生态环境进行了描述，杂草稻混生在深水稻中繁衍。种子休眠性研究表明，海南杂草稻的种子休眠性介于籼稻品种和野生稻之间，证实了这种杂草稻靠种子休眠可度过不良条件,从而繁衍下来。海南杂草稻为一年生草本，水生或陆生，形态上类似籼稻。对杂草稻的特征特性进行了描述，对其利用价值进行了探讨。

关键词: 海南岛杂草稻, 生态考察, 鉴定