Background and Aims:We evaluated the effectiveness of water jelly ingestion for both rehabilitation and the prevention of aspiration pneumonia in a retrospective analysis of elderly patients with moderate to severe dysphagia.Patients and Methods:Study 1: consecutive patients with borderline ingestion in an endoscopic swallowing evaluation were enrolled (n=36, 18 men and 18 women: mean age 82±9 y) and categorized into a group with water jelly (50 to 100 mL) ingestion training 3×/day or an untrained control group. Their food intake levels were then compared using a Food Intake Level Scale. Study 2: consecutive patients who were hospitalized because of aspiration pneumonia were enrolled (n=64, 35 men and 29 women: mean age 81±9 y) and categorized into a group with cyclic ingestion of water jelly immediately after each meal or a control group. The incidence of aspiration pneumonia that was newly developed during hospitalization was compared between the groups.Results:In study 1, 36 patients with a Hyodo-Komagane score of 8 were enrolled. Three of the 12 (25%) patients who underwent water jelly ingestion training were able to eat a pureed diet (level 5, 2 patients; level 6, 1 patient) while none of the 24 patients (0%) who did not undergo this training were able to eat any form of diet (levels 5 and 6, no patients) (P=0.011). In study 2, 64 patients were enrolled. No newly developed aspiration pneumonia was observed in the 34 patients (0%) who received cyclic water jelly ingestion, whereas 17% (5/30) of patients not receiving water jelly after meals newly developed aspiration pneumonia during hospitalization (P=0.031).Conclusions:Water jelly ingestion was effective for both rehabilitation and the prevention of aspiration pneumonia in elderly patients with moderate to severe dysphagia.