Abstract: In this paper the authors reviewed the characteristics in the different phases in the life cycle of ferns. Special attentions were given to the effect of light, plant growth regulators, water and temperature on the fern gametophyte development, and the effect of antheridiogen, light, calcium and other plant growth regulator on the formation and differentiation of fern sex organ. The labile sex expression in ferns was also discussed. In the light of the latest genetic and molecular biological research, we concluded that the ferns are suitable subjects for the purpose of biological study on plants.