Background <p>Cardiopulmonary exercise testing (CPET) parameters, such as ventilatory equivalent for carbon dioxide (V̇_E/V̇CO₂), peak oxygen consumption (V̇O_2peak), and anaerobic threshold (AT), have been proposed as potential predictors of postoperative complications. Yet, few systematic analyses have examined the association between CPET variables and major complications after esophagectomy, as defined by the Clavien–Dindo classification. Associations with cardiopulmonary complications and mortality also require updating on the basis of trial sequential analysis (TSA).</p> Materials and Methods <p>Systematic searches were conducted to identify relevant studies reporting preoperative CPET values and major complications, cardiopulmonary complications, and 1-year mortality. Standardized mean differences (SMD, random-effects model) were calculated and TSA was conducted to evaluate the robustness of evidence in the previous and current meta-analyses.</p> Results <p>A total of 12 studies met inclusion criteria. V̇O_2peak was correlated with major complications (SMD = − 0.42; 95% CI − 0.70 to − 0.14, <i>p</i> = 0.0032) and cardiopulmonary complications (SMD = − 0.39; 95% CI − 0.65 to − 0.13, <i>p</i> = 0.0032). AT showed similar but weaker associations with both outcomes (SMD = − 0.33 and − 0.22; 95% CI − 0.63 to − 0.03 and CI − 0.40 to − 0.04, <i>p</i> = 0.033 and 0.018, respectively). V̇_E/V̇CO₂ demonstrated no meaningful relationship with major complications. In addition, the present study found neither V̇O_2peak nor AT was associated with 1-year mortality after esophagectomy.</p> Conclusions <p>V̇O_2peak and AT were inversely associated with morbidity after esophagectomy, while V̇_E/V̇CO₂ offered limited prognostic value and none predict 1-year survival. V̇O_2peak is a key predictor of major and cardiopulmonary complications after esophagectomy and warrants further investigation, either alone or as part of a composite model.</p>