Aim: The aim of this study was to evaluate risk factors for proton pump inhibitor (PPI) resistance in older Japanese female patients with reflux esophagitis evaluated by physicians. Methods: The study included 462 Japanese female patients aged over 60 years with reflux esophagitis who received PPI maintenance therapy for more than 6 months. Results: The characteristics of all 462 patients were: age: 76.4 ± 7.6 years, height: 147.2 ± 6.1 cm, weight: 49.9 ± 8.4 kg and body mass index: 24.0 ± 3.5. The reflux esophagitis grades were A in 69.5%, B in 15.8%, C in 9.1% and D in 5.6%. Helicobacter pylori was positive in 60.6%. Regarding PPI maintenance therapy for clinical symptoms evaluated by the attending physicians, 66.7% were ‘good control’, 26.8% were ‘reasonable control’ and 6.5% were ‘bad control: resistant’. PPI maintenance therapy was less effective in patients with more severe reflux esophagitis of grades C and D (OR: 0.027; 95% CI: 0.010–0.077) and negative H. pylori infection status (OR: 4.470; 95% CI: 1.631–12.247). Lumbar kyphosis and hiatus hernia were risk factors for severity grading of reflux esophagitis. Conclusions: PPI maintenance therapy evaluated by attending physicians indicated that reflux esophagitis severity and negative H. pylori status were risk factors for treatment resistance.