There is provided a liquid ejecting apparatus for ejecting liquid to a printing material, having a platen for supporting the printing material, an ejection head for ejecting the liquid to the printing material by reciprocating on the printing material supported by the platen, an optical sensor reciprocating together with the ejection head and having a light emitting section for emitting light toward the printing material and the platen and a light receiving section for receiving light reflected from the printing material to optically detect whether or not the printing material exists, a usage measuring section for measuring usage of the liquid ejecting apparatus and a correcting section for correcting a result detected by the optical sensor based on the usage measured by the usage measuring section.