A cleaning method includes: supplying a cleaning gas in a processing container while continuously increasing a pressure in the processing container in a stepwise manner at a plurality of time points, thereby executing a cleaning of the processing container by removing a film deposited in the processing container; and detecting an end point of the cleaning based on time-dependent data of a concentration of a predetermined gas generated during the executing the cleaning, for each pressure of the plurality of time points. The executing the cleaning is implemented when the time-dependent data of the concentration of the predetermined gas generated in the continuously increasing the pressure changes from an increasing state to a decreasing state after exceeding a threshold value.