A white light source system configured to be capable of reproducing white light of a color temperature on a locus of blackbody radiation, and white light of a correlated color temperature with a deviation from the locus of the blackbody radiation. wherein P(λ), B(λ) and V(λ) satisfy an equation below in a wavelength range in which λ is 380 nm to 780 nm, and the white light source system satisfies an expression below in a wavelength range of 400 nm to 495 nm: ∫ 380 780 P λ V λ d λ = ∫ 380 780 B λ V λ d λ P λ / B λ ≦ 1.8. where P(λ) is a light emission spectrum of the white light emitted from the white light source system, B(λ) is a light emission spectrum of blackbody radiation of a color temperature corresponding to a color temperature of the white light, and V(λ) is a spectrum of a spectral luminous efficiency, and wherein the white light source system comprises one or two or more kinds of white light sources comprising an LED configured to emit primary light of ultraviolet to violet having a light emission peak wavelength of 360 nm to 420 nm, and a phosphor configured to absorb the primary light from the LED and to emit secondary light of white, and wherein the phosphor is a mixture of at least four kinds of phosphors selected from the group consisting of a blue-green phosphor, a blue phosphor, a green phosphor, a yellow phosphor, and a red phosphor, wherein the blue-green phosphor is at least one kind selected from among a europium activated strontium aluminate phosphor having a light emission peak wavelength of 480 to 500 nm, and a europium and manganese activated barium magnesium aluminate phosphor having a light emission peak wavelength of 510 to 520 nm, wherein the blue phosphor is at least one kind selected from among a europium activated strontium aluminate phosphor having a light emission peak wavelength of 480 to 500 nm and a europium activated alkaline earth phosphate phosphor having a light emission peak wavelength of 440 to 460 nm, wherein the green phosphor is at least one kind selected from among a europium activated orthosilicate phosphor having a light emission peak wavelength of 520 to 550 nm, and a europium activated β-sialon phosphor having a light emission peak wavelength of 535 to 545 nm, and a europium activated strontium sialon phosphor having a light emission peak wavelength of 520 to 540 nm, wherein the yellow phosphor is at least one kind selected from among a europium activated orthosilicate phosphor having an emission peak wavelength of 550 to 580 nm, and a cerium activated rare earth aluminum garnet phosphor having a light emission peak wavelength of 550 to 580 nm, and wherein the red phosphor is at least one kind selected from among a europium activated strontium sialon phosphor having a light emission peak wavelength of 600 to 630 nm, a europium activated calcium nitridoaluminosilicate phosphor having a light emission peak wavelength of 620 to 660 nm, and a manganese activated magnesium fluorogermanate phosphor having a light emission peak wavelength of 640 to 660 nm. wherein the white light source system comprises one or two or more kinds of white light sources comprising an LED configured to emit primary light of ultraviolet to violet having a light emission peak wavelength of 360 nm to 420 nm, and a phosphor configured to absorb the primary light from the LED and to emit secondary light of white, and wherein the phosphor is a mixture of at least four kinds of phosphors selected from the group consisting of a blue-green phosphor, a blue phosphor, a green phosphor, a yellow phosphor, and a red phosphor, wherein the blue-green phosphor is at least one kind selected from among a europium activated strontium aluminate phosphor having a light emission peak wavelength of 480 to 500 nm, and a europium and manganese activated barium magnesium aluminate phosphor having a light emission peak wavelength of 510 to 520 nm, wherein the blue phosphor is at least one kind selected from among a europium activated strontium aluminate phosphor having a light emission peak wavelength of 480 to 500 nm and a europium activated alkaline earth phosphate phosphor having a light emission peak wavelength of 440 to 460 nm, wherein the green phosphor is at least one kind selected from among a europium activated orthosilicate phosphor having a light emission peak wavelength of 520 to 550 nm, and a europium activated β-sialon phosphor having a light emission peak wavelength of 535 to 545 nm, and a europium activated strontium sialon phosphor having a light emission peak wavelength of 520 to 540 nm, wherein the yellow phosphor is at least one kind selected from among a europium activated orthosilicate phosphor having an emission peak wavelength of 550 to 580 nm, and a cerium activated rare earth aluminum garnet phosphor having a light emission peak wavelength of 550 to 580 nm, and wherein the red phosphor is at least one kind selected from among a europium activated strontium sialon phosphor having a light emission peak wavelength of 600 to 630 nm, a europium activated calcium nitridoaluminosilicate phosphor having a light emission peak wavelength of 620 to 660 nm, and a manganese activated magnesium fluorogermanate phosphor having a light emission peak wavelength of 640 to 660 nm.