There is emerging evidence supporting ventricular function as a prognostic factor in congenital diaphragmatic hernia (CDH). The present systematic review and meta-analysis aimed to determine the predictive value of early ventricular function for survival and extracorporeal membrane oxygenation (ECMO) requirement in newborns with CDH. PubMed, Google Scholar, Cochrane Central Register, Clinical Trial Registry, and Opengrey were accessed. Studies evaluating associations between echocardiographic ventricular function measured ≤ 48 h after birth and survival or ECMO requirement were included. Two independent authors extracted the following data: study and participant characteristics, prognostic factors, and outcome-related data. Eleven studies met the inclusion criteria. Five studies reported on survival, two on ECMO, and four on both outcomes. A moderate risk of bias was found in most of the studies, mainly because of selection, prognostic factors, and confounding biases. For survival (899 participants), pooled sensitivity and specificity were 86% (95% confidence interval [CI], 77–92%) and 44% (95% CI, 25–65%), respectively, in normal left ventricular function. For ECMO need (815 participants), pooled sensitivity and specificity were 39.8% (95% CI, 27–52%) and 88% (95% CI, 80–96%), respectively, in left ventricular dysfunction. Overall certainty of the evidence was graded very low for survival and low for ECMO. Inconsistent reporting of echocardiographic measurements and lack of adjustment for confounding factors were major limitations. Conclusions: Early ventricular dysfunction is a potential prognostic factor in CDH. Standardized echocardiographic measurement reporting and high-quality studies are needed to further elucidate its prognostic significance.