This invention provides a structurally-simple LED light source that is capable of preventing temperature variations among its multiple LED elements arranged densely on its LED-mounting substrate and also improving the heat release capabilities of the substrate by comprising an LED light source with: a plurality of LED elements each of which is formed by connecting an LED chip to electrodes formed on a ceramic substrate; an LED-mounting substrate on which to mount the plurality of LED elements, the LED-mounting substrate having through holes therein; and a heat sink plate for releasing heat from the LED-mounting substrate, wherein a thermally conductive resin is present between the LED-mounting substrate and the heat sink plate and wherein part of the thermally conductive resin protrudes from the through holes of the LED-mounting substrate and covers the top surface of the LED-mounting substrate on which the plurality of LED elements are mounted, so that the part of the thermally conductive resin is in contact with the plurality of LED elements.