Percutaneous mitral commissurotomy (PMC) was successfully performed in a 48-year-old woman with dextrocardia and situs inversus and a severe mitral stenosis. After PMC, the valve area increased from 0.97 to 1.89 cm2, and no complication occurred. This case shows that PMC is practicable in a case of dextrocardia with situs inversus. The procedure appears to be safer and easier when carried out with the inoue balloon, image inversion on the screen, and under transesophageal echocardiographic monitoring.