Objective: Abnormal circadian blood pressure rhythm has been revealed to be associated with hypertensive target organ damage and cardiovascular events, but its association with readmission risk in patients with heart failure with preserved ejection fraction (HFpEF) remains unknown. We conducted a retrospective study to explore the relationship between circadian blood pressure rhythm and readmission risk in HFpEF patients. Methods: We retrospectively collected baseline and follow-up data on HFpEF patients who underwent ambulatory blood pressure monitoring (ABPM) from May 2015 to October 2019. Patient circadian blood pressure rhythms defined by ABPM were grouped as dipper, nondipper, or riser patterns. Univariate and multivariate linear regression analyses were performed to assess the association between circadian blood pressure rhythm and readmission risk. Results: A total of 122 patients were enrolled in this study. The mean age and ejection fraction were 69.87 years and 61.44%, respectively, with mean the N-terminal pro-B-type natriuretic peptide (NT-proBNP) level being 1048.15 pg/mL. There were significant differences in the 24-hour systolic blood pressure (SBP), sleep SBP, and sleep diastolic blood pressure (DBP) among the three groups, where the 24-hour SBP, sleep SBP, and sleep DBP in the riser pattern group were markedly higher than in the dipper pattern group. Notably, serum NT-proBNP levels, the proportion of patients readmitted for heart failure and the mean number of admissions differed markedly among three groups. Instructively, multivariate linear regression analysis showed that the riser pattern was a significant and independent risk factor for increased serum NT-proBNP level (β = 929.16, 95% confidence interval 178.79–1679.53, P = 0.016). In multivariate logistic regression analysis, the riser pattern was demonstrated to be a significant risk factor for readmission (odds ratio 11.23, 95% confidence interval 2.01–62.67, P = 0.006) in HFpEF patients. Conclusion: The riser blood pressure pattern is a potential risk factor for elevated serum NT-proBNP level and readmission in HFpEF patients.