Objective To study the left ventricular mass index (LVMI) of patients with Parkinson’s disease and to explore the related factors. Methods Seventy-five clinically diagnosed PD patients were divided into two subgroups according to H-Y classification. In addition, 75 healthy controls matched for age and sex were involved. Relevant data were collected including age, sex, course of disease and madopar equivalent dose. Real-time three-dimensional ultrasound (RT-3DE) was used to measure LVMI and left ventricular function including left ventricular end-diastolic volume index (LVEDVI), left ventricular stroke volume index (LVSVI) and left ventricular ejection fraction (LVEF). These indexes were all measured in different PD subgroups and normal controls. Results LVMI of PD patients in middle and late stage was lower than that of early stage and control group (p<0.05). LVSVI, LVEF of PD patients in middle and late stage were lower than that of early stage and control group (all p<0.05). There were no significant differences in other indexes between PD subgroups or between PD group and healthy control group. Correlation analysis showed that there is an obvious negative correlation between LVMI and UPDRS score, disease duration and Madopar equivalent dose (r=-0.512, -0.438, -0.621, all p<0.05). Conclusions By using RT-3DE, LVSVI and LVEF and LVMI decreased in patients with intermediate and advanced PD. It can be seen that in the middle and late stages of the disease, the heart function of PD patients is also affected, which may be helpful to evaluate the degree of influence of PD on the heart.