Despite some visual colorimetric chemical logic gates having been reported, a complete set of six basic logic gates have not been realized to date. Moreover, the application of the reported logic gates needs to be further extended. Herein, the label-free molybdenum oxide nanomaterials are presented for the construction of a new visual colorimetric molecular computing system. A complete set of six basic colorimetric logic gates (OR, AND, NOR, NAND, XOR, XNOR) and the INH logic gate are realized based on plasmonic switching in MoO3 nanomaterials. In addition, the rational integration of different logic gates into a 1:2 demultiplexer circuit is also testified.