(EN) A modular cabinet storage system for toilets that has a modular outside design that allows it to be mounted onto a standard toilet water tank, and is shaped to match the tank so that it blends well with the existing toilet design for aesthetics. Its outside modular design also allows other modular cabinet storage units to be stacked above or below it. The modular cabinet storage system is modular internally as well, providing the means to allow a wide variety of modular subassemblies to be installed inside it, such as shelving, bins, drawers and panels. These subassemblies allow the storage system to provide storage space for articles and to help organize them for easy retrieval.