The purpose of this study is to ensure the stability of the arch structure, i.e. greenhouse, constructed by the experience. This paper dealt with a structural behavior of arch structure for vertical load with or without tie. The tie with or without pre-tension changes the action of the greenhouse frame to an arch action, and the resistance of the structure is increased. As results of using the tie, effect of the reinforcement is considered most appropriate when the stiffness of the tie is about 2 to 9 N/mm. And then, in the appropriate range of the stiffness of tie the maximum moment is reduced by 47% when compared without tie.