Abstract　 　 
We have been developing superconducting detectors for quantum detection of electromagnetic waves ranging from submillimeter and terahertz (THz) waves to X-rays. In this presentation, we will introduce our development on (i) X-ray to optical detectors using superconducting tunnel junction (STJ), (ii) THz detector using STJ, and (iii) MMW to THz detectors using microwave kinetic inductance detectors (MKIDs).We will explain about the principles of detection, detector design, actual experimental setup, recent results and future prospects.