To optimize the strength balance of a storage container with a stacked structure excellent in environmental suitability, and to provide a processing composition storage container for a silver halide photographic sensitive material which ensures improved strength of the storage container after long-term storage and improved storage suitability of a photographic processing agent.

The processing composition storage container for a silver halide photographic sensitive material is a container containing a processing composition for a silver halide photographic sensitive material and has a multilayer structure obtained by stacking at least two biodegradable plastics, wherein at least one of the biodegradable plastics has a flexural elasticity modulus of ≥1,000 MPa.