How plants survive and adapt to microgravity environments is highlight problem in space biology. Research progress on influences of microgravity and simulated micrograviy on plant growth and development is reviewed. The advance in studies on physiological and biochemical characteristic changes in microgravity or simulated microgravity environments is specially discussed. Experment evidence shows that calcium concentration and distribution changed under microgravity stimulate and then Ca2+ as a second message in transmission related enzyme activity. It is pointed out that further researches should focus on difference express of involved genes and mechanism and applications in such fields as germination of aging seed , accumulation of secondary metabolite and protoplasm fusion under microgravity environments.