With the development of minimally invasive techniques as well as surgical robotics, there has been an urgent demand for laparoscopic surgical robots that are small, low-cost and adaptable. This paper proposes a new design of minimally invasive surgical robot based on shape memory alloy (SMA)-actuated system which can provide flexible movement, large work space and powerful output. In the end, the performance of the robot system is conducted in vitro and in vivo tests.