Objective: To investigate the relationship between serum anti-endometrial antibody(EMAb), homocysteine(Hcy), folic acid, progesterone and habitual abortion.Methods: One hundred and twenty-three non pregnant women with a history of recurrent spontaneous abortion(two or more consecutive) treated in our hospital were selected as habitual abortion group. In the same period 123 cases of normal pregnant women(NP group) and 123 cases of normal non pregnant women(NNP group) were assigned to reference group. The results of EMAb, Hcy, folic acid and progesterone detection were analyzed and compared between the groups.Results: (1)The mean serum Hcy in habitual abortion group was significantly higher than that in the reference group. The mean folic acid and progesterone value were significantly lower than those in the reference group,the differences bing statistically significant(P<0.05). (2)In NP group, Hcy was negatively correlated with folic acid levels(r=-0.459, P=0.012), while Hcy in the habitual abortion group was positively correlated with folic acid levels(r=-0388, P=0.023). (3)The positive rate of EMAb in the habitual abortion group was higher than that of the two groups in the reference group with statistically significant difference(P<0.05). (4)Compared with the women less than 30 years old, the Hcy values in habitual abortion women of more than 30 years old were significantly higher and the levels of progesteron decreased significantly, the differences being statistically significant(P<0.05).Conclusion: The levels of EMAb, Hcy, folic acid and progesteron are associated with the outcome of early threatened abortion.