Abstract: A modular storage system is formed from a plurality of stackable cube-shaped or rectangular-shaped units. Each unit is locked to another adjacent unit with fasteners inserted through their side walls. Each cube modular unit is formed by four identical rectangular panels which face each other in a box-like configuration without a lid or bottom, There are a plurality of tabs and notches in the beveled surface of the abutting edges of each panel. The beveled top edge of each panel mates with the beveled bottom edge to form a miter joint and to allow the complementary tabs and notches in the edges to lock together to prevent lateral displacement. There are a pair of grooves near each edge to allow for a curved molding to slide into to lock the edges of the panels together. The inside wall of each panel has a series of channels to allow shelves to be positioned in the body of the cube. A hanging door can be placed in the front of the cube to conceal the shelving.