Objective To investigate the effect of left ventricular (LV) myocardial work on left atrial reservior function in hypertension patients with different grades of heart failure (HF). Methods A total of 78 hypertension patients admitted in Sixth Medical Center of Chinese PLA General Hospital from March to April 2022 were consecutively recruited in this study. According to European Society of Cardiology heart failure classification, 43 patients with normal heart function were assigned into control group, 8 patients with ejection fraction(EF) <50% into HF with reduced ejection fraction (HFrEF) group, and 27 with EF ≥50% into HF with preserved ejection fraction (HFpEF) group. Vivid E95 4D Cardiac Ultrasound Machine (GE) was used to acquire 2D and 3D echo images, and 4D auto LAQ was employed to calculate LA volume and LASr. Based on LV longitudinal strain and blood pressure, pressure-strain loop were calculated to obtain LV myocardial work indicators, including global work index (GWI), global constructive work (GCW), global waste work (GWW) and global work efficiency (GWE). SPSS statistics 23.0 was used for statistical analysis. Data comparison between two groups was performed using student′s t test, ANOVA or Chi-square test depending on data type. Pearson correlation coefficient and covariance analysis were applied to investigate the correlation between LV myocardial work indicators and LASr. Results The GWI and GCW values were significantly higher in the control and HFpEF groups than the EFrHF group (P<0.01). The GWW value in the EFrHF and HFpEF groups was obviously higher than that in the control groups (P<0.05). Statistical differences were observed in the GWE value between any two groups, and the lowest value was seen in the HFrEF group, and that of the control group was higher than the EFpHF group (P<0.01). There were notably difference in LASr among the three groups, with the control group having the highest and the EFrHF group the smallest (P<0.01). A liner relationship was observed between GWI and LASr in different groups, which was independent of grouping. After controlling the effect of GWI, ANOVA indicated that significant difference was seen in LASr among the patients with different cardiac function (F=9.46; P<0.01). The worse the cardiac function was, the lower the LASr. Conclusion For the patients with EF <50%, both GWI and GCW values are decreased, while GWW value is increased. The HFpEF patients still have normal LV myocardial work, though with increasing GWW and declining GCW. No matter which classification of HF, LASr is reduced with the decline of GWI. 3D LA reservoir strain can be used as one of indicators for evaluating left ventricular function in clinical practice.