This study was to investigate the cardiac function characteristics under two-dimensional ultrasound and triplane tissue Doppler imaging (TDI) of patients with severe preeclampsia (SPE). 28 SPE patients with singleton pregnancy from January 2018 to December 2020 were included in the SPE group. 25 healthy nonpregnant women of reproductive age were taken as the control group (Ctrl group), and 26 normal pregnant women with singleton pregnancy were selected as the normal group (Norm group); all the research objects underwent ultrasonography. The morphological and functional indexes of left and right ventricles were compared among the cases in different groups. The results showed that the left ventricular end-diastolic period diameter (LVEDd), left ventricular relative wall thickness (LV-RWT), left ventricular mass index (LVMi), left anterior descending (LAd), left ventricular E/e and e/a values, right ventricular diameter (RV-D), right ventricular anterior wall thickness (RVAW), a value, right atrial septum (RA-S), pulmonary artery systolic pressure (PASP), left ventricular end-systolic period diameter (LVEds), interventricular septal thickness (IVSd), posterior wall thickness (PWd), end-diastolic period volume (EVD), end-systolic period volume (ESV), relative wall thickness (RWT), sphericity index (SpI), left atrium volume index (LAVi), and E/e value of patients in the SPE group were higher than those in the Ctrl group and the Norm group (P < 0.05). The mitral annular plane systolic excursion (MAPSE), s value, tricuspid annual plane systolic excursion (TAPSE), ratio of early diastolic blood flow velocity to late diastolic blood flow velocity (E/A), ratio of peak early diastolic velocity to peak late diastolic velocity (e/a), peak early diastolic velocity (e), and ejection fraction (EF) of the SPE group were lower than those of the Ctrl group and the Norm group (P < 0.05). The ratio of mitral valve early diastolic blood flow velocity to peak early diastolic velocity (E/e) of the Norm group was higher than that of the Ctrl group (P < 0.05). In two-dimensional ultrasound of the SPE group, the maximum difference in time from the start to the peak of systole (Ts) of the right ventricle between the basal and middle segments of the lateral wall and that of interventricular septum (RV-Ts-max) was 31.56 ± 0.39%. The maximum difference in time to peak of early diastole (Te) under the same condition (RV-Te-max) was 47.16 ± 0.19%. Left ventricular LV-Ts-max and LV-Te-max were 9.83 ± 0.80% and 8.37 ± 0.68%, respectively, in triplane TDI, which were considerably higher than those in the Ctrl and Norm groups (P < 0.05). It suggested that two-dimensional ultrasound and triplane TDI could reflect the ventricular morphology as well as diastolic and systolic function injury in patients, which offered a reference basis for the diagnosis of SPE.