PURPOSE: To obtain a processing method of a silver halide color photosensitive material featuring high safety and environmental adaptability by charging solid processing agents substantially directly into at least one of the processing tanks of an automatic developing machine.

CONSTITUTION: The projecting part of a sliding cap 334 is prevented from descending by an opening/closing regulating member 35 when a housing container 33 mounted at a housing container packing means 34 is depressed in a direction C from an initial position until the container arrives at an intermediate position. The sliding cap 334 is held stopped and, therefore, when the housing container 33 is further oscillated downward, the aperture of the outlet member 332 of the housing container 33 is gradually opened. The aperture of the outlet member 332 is fully opened when the descending of the housing container 33 arrives at a prescribed position and is stopped. The solid processing agent J in the foremost row in the housing container 33 is sent into a supplying means 35. The exchange operation of the housing container 33 is executed by generation of a residual amt. detection signal when the solid processing agents J in the housing container 33 are successively consumed until no more agents are left.