The invention provides a connection release mechanism driven through large-stroke large-load shape memory alloy and belongs to the technical field of connection release mechanisms capable of being repeatedly used. According to a driving mode of the mechanism, SMA alloy wires and a lever principle are mainly used for first-level stroke amplification and second-level load amplification, an inner cylinder is driven to move, constraint of partial nuts is released, bolts are released, and the separation and release aim between two components or among assemblies under the large-stroke large-load working condition is achieved. Through a heating contraction characteristic of the SMA alloy wires, the release function is achieved, when heating is stopped, the system pushes the inner cylinder to reset under the effect of a pre-compressed bias spring, and accordingly the mechanism is reused. The mechanism is suitable for large-stroke large-load release and is high and stable in bearing capacity and high in anti-shock and anti-impact capacity and reliability.