In the pressure control of a pneumatic drive system, there is a possibility that leads to hazard (accident) based on the ejection of high pressure air, the rupture of the vessel, etc. Many of these accidents are caused by the hazard side error by the control, or caused by the hazard side failure of the various components in the system. To cope with these problems, the interlock system proposed by the authors in 2013 can eliminate the hazard side failure in the pneumatic drive system. This interlock system is constructed according to the principles of the safety (confirmation). But, a shutdown at an interlock operation is an inevitable state. At the same time, unnecessary shutdowns should be avoided. Therefore, in accordance with the principles of safety (confirmation), the control strategy is demanded strongly for creating the safety conditions to give the interlock system the operation permission. In this study, our considerations devoted into the pressure control of the pneumatic drive system. First of all, the shutdown structure was defined by using our interlock system. Next, the regulating safety control was designed to create a safe condition. Finally, as a condition of safety control, the purpose control of pneumatic drive system was examined. Here, the safety control strategy consisting of three of the purpose control, the regulating safety control, and the interlocks discussed.