Five kinds of seeds of beardless Iris species were used as materials. The purpose of this study was to understand the reasons of seminal dormancy and germination method through conducting the absorbent and germination experiments. This can provide technical support for the protection and application of Iris germplasm resources. The results are as followed: (1) the results of waterabsorbing of five wild Apogons Iris seed showed that the water permeability of I. ensata Thunb. and I. setosa Pall. was the best, followed by I. laevigata Fisch, while the water permeability of I. sanguinea Donn. ex Horn. was poor. The permeability to water and gas and density of the endosperm is one of the main reasons for the inhibition of seed germination of I. lactea Pall. var. chinensis Kodiz.. In contrast, the dense endosperm is the main factor affecting the germination of the seeds. and the alternating temperature can increase the permeability of the seed coat and endosperm. (2) There was a strong inhibitory effect on seed coat of I. lactea Pall. var. chinensis Kodiz. and I. sanguinea Donn. ex Horn. for germination, while the inhibition of seed cost of I. laevigata Fisch.,I. ensata Thunb.and I. setosa. Pall.was not significant. The tipped micropylar endosperm is the main factor in the dormancy of five wild Iris. (3) The effects of temperature influenced seed germination of Iris greatly, alternating temperature significantly or very significantly increased seed germination rate of I. lactea Pall. var. chinensis Kodiz., I. sanguinea Donn. ex Horn., I. ensata Thunb., and the optimum alternating temperature was 30 ℃/20 ℃, 8 h light/16 h dark, but seed germination rate, germination energy of I. setosa Pall.and I. lactea var. chinensis Kodiz. had not significant difference, therefore, the single factor could not break the seed dormancy of I. laevigata Fisch. and I. setosa Pall.. A study found that seed dormancy and germination characteristics in five species of wild Apogons Iris were different, the main influencing factors were different, but the tipped micropylar endosperm is the main factor in the dormancy of five wild Iris. It needed to adopt comprehensive measures with cold stratification combined alternating temperature 30 ℃/20 ℃, which was the effective measures on breaking seed dormancy to greatly enhance the wild Apogons Iris seed germination rate.