Dimorphic seeds may help plants to cope with unpredictable environmental changes, especially for halophytes. Mature seeds (black and brown) of Suaeda salsa inhabiting in the Yuncheng Salt Lake were used to reveal adaptive strategies of the halophyte with dimorphic seeds in saline habitat by combining laboratory observation and germination experiments. The morphology, dormancy and germination characteristics of dimorphic seeds were compared. The results showed that: (1) black seeds were small and had keratose and glossy testa, while brown seeds were larger and had membranous and lusterless testa. (2) Germination of freshly matured brown seeds was more than 90% across the experimental temperature ranges, while germination of black seeds was only the highest at 15/25 ℃ (less than 85%), and brown seeds had higher germination rate than black seeds. (3) Alternating of light and darkness or full darkness had no significant effect on germination of brown seeds under low salt conditions (<0.39 mol/L). However, germination of black seeds under light was significantly higher than that under darkness (P＜0.05). Responses of dimorphic seeds to saline stress were different, germination of brown seeds was more than 30% in 0.78 mol/L NaCl solution, while black seeds did not germinate beyond 0.59 mol/L. (4) Brown seeds were nondormant, but black seeds had nondeep physiological dormancy. Seed coat scarification, dry storage, cold stratification and GA₃ significantly promoted germination of black seeds. Our study revealed that S. salsa adopts “bethedging” strategy (differences in dormancy and germination behavior of dimorphic seeds) to increase the adaptability to the heterogeneous habitat.