Some space structures have critical vibration problems owing to their low stiffness and low damping. And some traditional displacement control methods are no longer suitable to the space structures because they are hard to install. A new way to solve this problem has been introduced. Both the dynamical strain equation and the strain control state equation have been developed. A cantilever beam has been taken as an example. Numerical simulation has been done. The results show us that the vibration strain control is of great significance.