Mechanoluminescent (ML) material is a novel functional material and it can emit intensive light emission repeatedly with weak stress application excising in our ordinary life. The ML materials are powder of ceramics, and as the characters one by one particle itself is stress sensor and emitting material. In addition, recently, we succeeded to synthesize the ML nanoparticle with the size of 10 nm, and it is enough small to inject and use in bio-body. From these viewpoints, we believe that our ML nano- or micro- particle can be used as an ubiquitous light source even in the dark bio-tissue and cell. For the purpose, we have investigated mechanoluminescence induced by ultrasonic wave, non-destructive and non-inventive stimulation for bio-tissue, and we successfully detect the mechanoluminescence.