To figure out the optimal strategy to manage Tetralogy of Fallot (TOF) with unbalanced pulmonary artery(PA) branches by investigating the different effects of PA plasty on the development of the hypoplastic PA (HPA). A single center, retrospective analysis was carried out to compare the outcome of different PA plasty methods on the development of HPA in patients of TOF with unbalanced PA branches. Size and balance of the PA branches were used to evaluate the outcome of PA plasty. In the NATIVE group, 100% of the HPAs were well-developed and all the PA branches became balanced, while in the PATCH and EXTENSION groups, the percentage of well-developed HPAs was 40% and 33%, respectively, and none of the PA branches were balanced. In addition, HPAs became atretic in 28% of the patients in the patch enlargement group. For TOF with unbalanced PA branches, patch enlargement may not be a good treatment strategy, as it reduces the growth potential of HPA and even causes iatrogenic atresia. Leaving the HPA in the native state without patch enlargement may be a good strategy.