Objective 2D-STI was used to evaluate the relationship between atrial septal thickness and left atrial structure and function in patients with essential hypertension. Methods Forty one patients with hypertension (LAR 20 cases in left atrial remodeling group and 21 cases in left atrial non remodeling group) and 25 healthy subjects were enrolled in this study, The mean strains rates (mSRs, mSRe, mSRa) of left atrial wall and atrial septum were measured by 2D-STI technique. RT-3DE (real-time three-dimensional volume imaging) combined with ECG phase was used to obtain the left atrial maximum volume (LAVmax), left atrial pre systolic volume (LAVpre), left atrial minimum volume (LAVmin), and the left atrial passive emptying index (LAEFpassive), left atrial active emptying index (LAEFactive) and left atrial dilation index (LAEF) were calculated.Systolic atrial septal thickness (IASTs) and diastolic atrial septal thickness (IASTd) were measured by M-mode ultrasound, and the atrial septal thickening rate (ASTDF (%) ) was calculated.The correlation between the thickening rate of atrial septum and left atrial active emptying index, average late diastolic strain rate and total left atrial emptying fraction was analyzed.Results Compared with the control group, The levels of mSRs, mSRe, LAEFp and LAEF in the LAN group were all decreased. mSRa,LAEFa and ASTDF all increased, P <0.05, and the difference was statistically significant. The LAR group is compared to the LAN group, mSRs, mSRe, LAEFp and LAEF were all decreased with P <0.05.There was a significant positive correlation between atrial septal thickening rate and left atrial active emptying index, average late diastolic strain rate and left atrial total emptying fraction (P < 0.05).Conclusions The left atrial function has begun to decline in patients with hypertension at the early stage. The thickness and thickening rate of atrial septum have significant positive correlation with left atrial function. Atrial septal thickness and thickening rate can be used as supplementary predictors of early changes in left atrial function.