Objective: Previous studies showed acromegaly have significant higher prevalence of ventricular arrhythmias and often complicated by diabetes mellitus (DM) and hypertension (HT). Both HT and DM are notoriously associated with the development of arrhythmias. However, the effect of complication (DM and/or HT) in acromegaly on ventricular arrhythmias and the risk of ventricular arrhythmias in acromegaly accept therapy but no control is largely unknown. Methods: A cross-sectional study with 307 acromegaly and 303 patients with non-functional pituitary adenoma as control group. All subjects divided into acromegaly with/without complication and controls with/without complication. In the longitudinal study, 30 persistent uncontrolled active acromegaly with at least three months follow-up. Electrocardiographic Measurements, laboratory examination, and clinical data collection performed in all subjects. QT interval corrected for heart rate (QTc) analysed among groups. Results: QTc in acromegaly population significantly increased compared to controls (p<0.001). Factorial design twoway ANOVA correcting age revealed significant main effects of complication (p=0.016) and acromegaly (p<0.0001), as well as positive interactions between complication and acromegaly (P<0.038) on QTc. Persistent uncontrolled active acromegalic patients after therapy showed QTc significantly increase in follow-up relative to pre-treatment (p<0.0001). The normalized GH level (r=0.11, p<0.05) and complication (r=0.25, p<0.0001) have a significant positive correlation with QTc in acromegaly. Conclusions: Acromegaly is an independent risk factor for ventricular arrhythmias and acromegaly with complication have an elevated risk for ventricular arrhythmia. Persistent uncontrolled acromegaly, who have significantly decreased in serum GH/IGF-1 levels relative to pre-treatment, also enhance the risk of ventricular arrhythmia.