Introduction: Mini invasive mitral valve surgery had some advantages over conventional surgery in recovery and cosmestic results. Postoperative pain was an interested factor for comparing these two methods, with reported results remained unclear. We realized this study for evaluate the characteristics of postoperative pain between mini invasive and conventional mitral surgery in Hanoi Heart Hospital.
 Methods: A cross sectional study on patient underwent mitral valve replacement with mini invasive and conventional sternotomy approach.
 Results: There were 66 patients in the study, divided into 2 group: 43 patient underwent conventional surgery and 23 patient underwent mini invasive surgery. Mean age was 50,7 ± 9,3, female was 78,8% and mean BMI was 20,9 ± 2,7. Erector spinae plane (ESP) block was performed on 16 patients (24,2%) of conventional surgery group. The VAS score at 3 days, 7 days , and 1 month after surgery was 7,7 ± 1,2; 5,2 ± 1,5; 0,9 ± 1,1 in sternotomy group and 6,6 ± 1,6; 3,8 ± 1,5; 1,7 ± 0,9 in mini invasive group, respectively. In patients with ESP block, mean dose of morphine administered in first two days was 0 and 2,3 ± 5,0 mg/kg comparing to the dose of 19,7 ± 5,5 và 17,7 ± 7,1 in sternotomy patients without ESP block.
 Conclusions: Postoperative pain reduction may not be an advantage of mini invasive mitral surrgery comparing to conventional surrgery, but the time for pain suffering in this group was shorter. ESP was an efficient method for early pain reduction after conventional surgery.