Abstract: A quasi-conforming or hybrid/mixed 9-node quadrilateral degenerated shell element CSH9 has been developed based upon the Hu-Washizu variational principle and the concept of degenerated solid shell element. This shell element is completely free from shear and membrane locking phenomena.It passes the patch test. The spurious Kinematic modes are globally suppressed. Numerical tests indicate that the shell element is highly accurate and effective.