For the past 30 years,percutaneous balloon mitral valve dilatation has been performed under the guidance of X-rays and bedside ultrasound.However,there are still some cases of mitral valve stenosis in the large atrium where balloon dilation failed.Intraperitoneal ultrasound-guided percutaneous balloon mitral valve plasty is accurate and feasible,which can reduce the occurrence of complications and improve the success rate of such elderly complex cases.Two patients with severe mitral stenosis underwent percutaneous balloon mitral valve plasty guided by intracardiac ultrasound.The operations were successful without any complications,which can provide reference for clinical treatment of mitral stenosis.