We have developed detachable Cavitas sensors into human cavitas sites of oral cavity for non-invasive monitoring of saliva glucose. A salivary biosensor based on the integration of Pt and Ag/AgCl electrodes with an enzyme membrane on a mouth guard was developed and tested. This mouth guard type biosensor was integrated with a glucose sensor and wireless measurement system. The electrodes were formed on the mouth guard surface which made of a polyethylene terephthalate glycol (PETG). The Pt working electrode was coated with the glucose oxidase (GOD) membrane. In the investigation of in-vitro characterization, the biosensor showed excellent relationship between the output current and the glucose concentration. In artificial saliva consisting of salts and proteins, the glucose sensor exhibits high-sensitive detection in a range of 5-1000 μmol/L. We demonstrated the capability of the sensor and wireless communication module to characterize an inclusion in oral phantom that imitative structure of human oral cavity. Stable and long-term monitoring (more than 2 hours) using telemetry system was established. The mouth guard biosensor would be useful for real-time and non-invasive method as a novel health care management.