Provided is a substrate processing apparatus wherein, even if a trouble occurs, it is bound to continue a process for the substrate without stopping the substrate processing apparatus entirely. The substrate processing apparatus according to the present disclosure includes first and second substrate conveying devices configured to convey wafers, and first and second processing blocks provided on the right and left sides of the substrate conveying device and having processing unit arrays each configured to perform the same process. Processing unit arrays on one side and processing unit arrays on the other side are respectively connected to a processing liquid supply system commonly provided with them. And, when any one of substrate conveying devices, processing liquid supply systems has a problem, the process for the wafer can be performed in the processing unit array to which the substrate conveying device and the processing liquid supply system under normal operation belong.