Objective Investigate the clinical efficacy of extracorporeal membrane oxygenation（ECMO） in the management of pregnant females complicated with critical cardiovascular diseases. Methods Clinical data of 6 pregnant patients with critical cardiovascular diseases treated by ECMO from 1 Jan 2014 to 30 Sept 2022 in our institution were analyzed by SPSS17.0 statistical software. Results 6 patients received ECMO. Patients′ ages ranged from 19 to 32 years old（median age 23.5 years old）. Gestation transferred ranged from 7 to 32 weeks（median gestation week was 29 weeks）. 3 patients were primigravid. 3 patients were in their second pregnancy，2 of which had a previous history of vaginal delivery. 3 patients were complicated with severe pulmonary hypertension，2 of which were idiopathic，and the other was secondary to rheumatic valvular heart disease. Other patients were compli⁃ cated with acute severe myocarditis，peripartum cardiomyopathy，and acute pulmonary heart disease respectively. Cesarean sections were performed in 3 patients and hysterotomy was performed in one patient. A multi⁃para patient had a spontaneous preterm delivery and a patient had an artificial abortion. Indications for ECMO were pulmonary hypertensive crisis ，cardiogenic shock ，and cardiopulmonary arrest. The duration of ECMO ranged from 4 to 16 days（median duration 7 days）. Major complications of ECMO included hemorrhage（3/6），infection（3/6）， multiple organs dysfunction syndrome（MODS，3/6），and thrombosis（2/6）. 5 patients suffered two of the above. 4 patients survived after ECMO with an average hospital stay of 28.25 days，and 2 patients died of MODS compli⁃ cated with severe infection or hemorrhage. 4 neonates survived with a good prognosis. Conclusions With the man⁃ agement of the multidisciplinary team，the timely application of ECMO in appropriate cases could provide sufficient life support and contribute to better maternal and fetal outcomes. Particularly in obstetric patients with critical car⁃ diovascular diseases，ECMO may play a vital role in the salvage treatment.