We aimed to investigate the prognostic value of three-dimensional right ventricular free wall longitudinal strain (3D-RV FWLS) in adult heart transplantation (HTx) patients, taking three-dimensional left ventricular global longitudinal strain (3D-LV GLS) into account. We prospectively enrolled 155 adult HTx patients. Conventional right ventricular (RV) function parameters, two-dimensional (2D) RV FWLS, 3D-RV FWLS, RV ejection fraction (RVEF), and 3D-LV GLS were obtained in all patients. All patients were followed for the endpoint of death and major adverse cardiac events. After a median follow-up of 34months, 20 (12.9%) patients had adverse events. Patients with adverse events had higher incidence of previous rejection, lower hemoglobin, and lower 2D-RV FWLS, 3D-RV FWLS, RVEF and 3D-LV GLS (P < 0.05). In multivariate Cox regression, Tricuspid annular plane systolic excursion (TAPSE), 2D-RV FWLS, 3D-RV FWLS, RVEF and 3D-LV GLS were independent predictors of adverse events. The Cox model using 3D-RV FWLS (C-index = 0.83, AIC = 147) or 3D-LV GLS (C-index = 0.80, AIC = 156) was observed to predict adverse events more accurately than that with TAPSE, 2D-RV FWLS, RVEF or traditional risk model. Moreover, when added in nested models including previous ACR history, hemoglobin levels, and 3D-LV GLS, the continuous NRI (0.396, 95% CI 0.013 ~ 0.647; P = 0.036) of 3D-RV FWLS was significant. 3D-RV FWLS is a stronger independent predictor of adverse outcomes, and provides additive predictive value over 2D-RV FWLS and conventional echocardiographic parameters in adult HTx patients, taking 3D-LV GLS into account.