This paper proposes a micro pneumatic suction device for medical diagnosis and operation. We are interested in the practical applications of medical MEMS devices to minimally invasive medical operation. Guaranteeing relative positioning between medical MEMS and the pulsative object in the body is becoming indispensable. The micro suction device is proposed to fix the medical MEMS on a surface of the pulsating target part. This paper describes the suction device integrated with medical MEMS. A temperature sensor and micropump for DDS are integrated with the suction devices as typical sensor and actuator. An in- vitro experiment validated the feasibility of the proposed suction device as an assistive medical interface. Furthermore, an in- vivo trial of local DDS and local temperature sensing were successful. The proposed micro pneumatic suction device for medical diagnosis and operation will contribute to practical application of medical MEMS devices.