The present invention provides a minimally invasive surgical instrument with a terminal steerable mechanism, comprising an intervention device, a control device and one or more wires. The strip-shaped intervention device sequentially includes a main section, a flexible section and an operation section from the top to the end. The control device includes a sphere with a preset rotational degree of freedom, and an operating lever connected to the sphere. Said one or more wires are extended along the main section of the intervention device. Here, the second ends of said at least one or more wires are connected to the flexible section or the operation section of the intervention device, and the first ends thereof are connected to at least a part of the control device.