Objective: To investigate the association between the preterm birth and low birth weight and parental thalassemia. Methods: Pregnant women and their husbands receiving prenatal examination in local hospitals or maternal and child health centers in Jingxi and Debao in Guangxi from January to December 2017 were selected as study subjects. A total of 758 pregnant women with pregnancy outcomes and their husbands, who were both or alone diagnosed with thalassemia through thalassemia gene detection, were selected as case group and 758 pregnant women with pregnancy outcomes and their husbands, who were negative in thalassemia gene detection and hemoglobin electrophoresis test were selected as control groups. The case group were further divided into mother group, father group and both mother and farther group. Clinical and pregnancy outcome data of the study subjects were collected for the analysis on the association between parental thalassaemia and preterm birth or low birth weight by the independent sample t test, χ² test and Cox regression analysis. Results: The incidence of preterm birth in case group and control group was about 6.5% and 1.6% and the incidence of low birth weight in case group and control group was about 7.3% and 0.8%. After adjusting for possible confounding factors, Cox regression analysis results showed that mother suffering from thalassemia (aRR=3.45, 95%CI: 1.35-8.81, P=0.010), fathers suffering from thalassemia (aRR=4.93, 95%CI: 2.16-11.21, P<0.001) and both mother and farther suffering from thalassemia (aRR=5.13, 95%CI: 2.62-10.04, P<0.001) were associated with preterm birth. Mother suffering from thalassemia (aRR=12.98, 95%CI: 4.91-34.30, P<0.001), fathers suffering from thalassemia (aRR=9.40, 95%CI: 3.40-25.95, P<0.001) and both mother and farther suffering from thalassemia (aRR=10.74, 95%CI: 4.44-26.00, P<0.001) were associated with low birth weight. The newborn whose parent all suffered from thalassemia had higher risks for preterm birth (χ²=22.72, P<0.001)and low birth weight (χ²=34.03, P<0.001) compared with those only with mother or father suffering from thalassemia. Conclusion Parental thalassaemia, including both sides and single side, might increase the risks of preterm birth and low birth weight for newborn, and the risks might be higher in newborn with both mother and father suffering from thalassaemia.