Background: Clinical characteristics of patients with heart failure may vary geographically. However, limited data are available regarding the geographical differences of patients with heart failure and preserved ejection fraction. Aims: The present subgroup analysis aims to investigate the geographical differences in clinical characteristics, management, and primary etiology of patients with heart failure and preserved ejection fraction in Turkey. Study Design: A cross-sectional study. Methods: A comPrehensive, ObservationaL registry of heart faiLure with mid-range and preserved ejection fractiON (APOLLON) is a multicenter and observational study conducted in seven regions of Turkey (NCT03026114). The present study is a post-hoc analysis of the APOLLON registry. In this substudy, we compared the clinical characteristics of 819 consecutive patients with heart failure and preserved ejection fraction (mean age, 67 years; 57.8% women) admitted to cardiology outpatient units in different geographical regions. Results: Based on the geographical distribution of the entire Turkish population, the highest number of patients enrolled were from Marmara (271 patients, 33.1%). All demographical characteristics, clinical and laboratory findings, comorbidities, primary etiology, and medications prescribed were significantly different between the regions. Furthermore, inter-regional gender differences were identified. Comparatively, the Aegean and Mediterranean regions had older patients with heart failure and preserved ejection fraction (p