Abstract: To study 2 ecotypes of Portulaca oleracea seeds’‘( Dahua’and weed) tolerance to saline and alkaline land, effect of different seawater concentrations on the germination of 2 ecotypes of P. oleracea seeds and their root and shoot length were studied. The results showed that: at the low seawater concentration (0-10%) the seed germination of 2 ecotypes of P. oleracea had no obvious difference. The concentration of above 10% significantly inhibited the seeds germination. When the concentration reached 50%, the seed germination of 2 ecotypes of P. oleracea was seriously inhibited. At per concentration of seawater, the germination rate, vigor index, germination index and root and shoot length of‘Dahua’P. oleracea were all higher than that of weed P. oleracea, indicating higher tolerance of seawater stress.