Disclosed is a versatile silicone resin reflective substrate which exhibits high reflectance of high luminance light from an LED light source over a wide wavelength from short wavelengths of approximately 340 - 500nm, which include wavelengths from 380 - 400nm near lower limit of the visible region, to longer wavelength in the infra-red region. The silicone resin reflective substrate also exhibits superior thermal conductivity, light fastness, heat resistance, weather resistance, and flame resistance without deterioration such as yellowing caused over time by the irradiation of the high luminance light. The silicone resin reflective substrate further exhibits mechanical and chemical stability, the ability to maintain a white color over a long period of time, and superior adhesion to metals and resins. The silicone resin reflective substrate can be easily formed as a wiring substrate, a packaging case or the like, and can be manufactured at low cost and a high rate of production. The silicone resin reflective substrate (10 €¢ 20) has a reflective layer which contains a white inorganic filler powder (12a €¢ 12b) dispersed in a three-dimensional cross linked silicone resin, the inorganic filler powder having a high reflective index than the silicone resin. The reflective layer is formed on a support body as a film, a solid, or a sheet.