A 3.5kg, 8-month-old Ragdoll cat was admitted to the veterinary hospital with symptoms of rapid breathing and abdominal breathing. After examination by a veterinarian, the cat was diagnosed with hypertrophic cardiomyopathy, as evidenced by left atrial enlargement, myocardial thickening, and poor systolic function. Additionally, the cat had pulmonary edema and pleural effusion.