Disclosed is a processing apparatus that includes a chamber accommodating a workpiece, a nozzle provided within the chamber, a measuring unit measuring the supply flow rate of the processing fluid supplied to the nozzle, an opening/closing unit performing opening/closing of the flow path of the processing fluid, and a controller. The controller sends an opening/closing operation signal that causes the opening/closing unit to perform an opening/closing operation according to recipe information that indicates processing contents. After sending the opening/closing operation signal to the opening/closing unit according to the recipe information, the controller starts the integration of the supply flow rate based on the measurement result of the measuring unit, monitors the rise of the supply flow rate based on the calculated integrated amount, and when supplying a specific flow rate, monitors the supply flow rate based on a value actually measured by the measuring unit.