Abstract: Objective To investigate the predictive values of electrocardiogram P wave dispersion (PWD) and P wave peak time in lead Ⅱ (PWPT Ⅱ) for new-onset atrial fibrillation in patients with essential hypertension. Methods A total of 120 essential hypertension patients diagnosed as new-onset atrial fibrillation in the First People's Hospital of Changzhou City from July 2021 to June 2023 were selected as atrial fibrillation group, and 240 essential hypertension patients without atrial fibrillation in the same period matched by age and gender were selected as control group. Electrocardiograms under sinus rhythm were obtained from the patients in the last year through the electronic medical record system. The basic clinical data and electrocardiogram indexes were compared between the two groups; the correlations of PWD and PWPT Ⅱ with new-onset atrial fibrillation in patients with essential hypertension were analyzed by binary Logistic regression; the receiver operating characteristic (ROC) curve was drawn, and the intra-observer and inter-observer agreement tests were conducted by the intra-class correlation coefficient (ICC). Results Heart rate (HR) of the atrial fibrillation group was significantly lower than that of the control group, while the body surface area (BSA), PR interval, PWD and PWPT Ⅱ were significantly higher than those of the control group (P<0.05). After adjusting for confounding factors (age, gender, HR, body mass index, BSA), binary Logistic regression analysis showed that PWD (OR=1.124, 95%CI, 1.095 to 1.155) and PWPT Ⅱ (OR=1.252, 95%CI, 1.186 to 1.320) were significantly associated with new-onset atrial fibrillation (P<0.001). ROC curve analysis showed that the area under the curve (AUC) of PWD and PWPT Ⅱ for predicting new-onset atrial fibrillation in patients with essential hypertension was 0.892 and 0.797 respectively, and the AUC of combined prediction by PWD and PWPT Ⅱ was 0.910. Both the intra-observer and inter-observer agreement for PWD and PWPT Ⅱ measurement were excellent (ICC>0.9). Conclusion Electrocardiogram PWD combined with PWPT Ⅱ has high application value in predicting new-onset atrial fibrillation in patients with essential hypertension.