MAV (Micro Air Vehicle) can be used for many applications such as the investigation of inhospitable environments, regions contaminated by nuclear pollution or hazardous material and other inaccessible areas. For such kind of purposes, a small machine that can autonomously fly seems to be appropriate. Our MAV research group selects a Quad-Rotor MAV as our platform, and achieved automated take-off, landing, hovering, way-point navigation, vision-based navigation flight. However, the payload of our current platform is low (about 500grams), and the flight duration is only about 10 minutes. To overcome these obstacles, we designed a Six-Rotor type MAV with 770mm of diameter, 1.9Kg of weight, 1.5Kg of payload and 12 minutes of flight duration (without payload). In this paper, we present the main design considerations which are essential for the construction of Six-Rotor type MAV and attitude controller design technique.