The purpose of the study is to evaluate right ventricular (RV) regional and global systolic function in patients with pulmonary arterial hypertension (PAH) by 2-dimensional ultrasound speckle tracking echocardiography (STE) and explore the impact of pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance (PVR) on RV systolic function. 42 patients with PAH and 31 healthy controls were included in this study. RV longitudinal peak systolic strain (LS) and strain rate (LSRs) were measured at the basal, mid and apical segments of the RV free wall and septum by STE. RV global longitudinal peak systolic strain (GLS) and strain rate (GLSRs) were also measured by STE. RV ejection fraction (EF) was determinated by cardiac magnetic resonance (CMR) imaging. LS and LSRs of RV 6 segments were significantly reduced in patients with PAH compared with controls. RV GLS and GLSRs were lower in patients with varying degrees of PAH than controls. Furthermore, RV GLS were most altered in patients with severe PAH compared with mild PAH. PVR was correlated with RV GLS and GLSRs (r₁ = -0.549; r₂ = -0.466, respectively, P < 0.05). Similarly, there was correlation between PASP and RV GLS and GLSRs (r₁ = -0.551; r₂ = -0.425, respectively, P < 0.05). GLS and GLSRs were correlated with CMR-derived RVEF. (r₁ = 0.693; r₂ = 0.560, respectively, P < 0.05). STE can identify impaired RV regional and global systolic function in patients with PAH. STE-derived strain and strain rate can be used as novel indices for RV function assessment from 2-dimensional echocardiographic images.