This paper describes high rigidity technology of the cabinet for large-sized Projection TV (PTV). I have executed the structure analysis by using the design model of 73" PTV. In the result of the analysis, the molding cabinet did not obtain enough rigidity. Then we have examined the best reinforcement structures for the PTV. As the result, we have decreased deformation of cabinet to one-eighth by the self-weight and to one-fifth by twist force.