Provided are a phosphor, a phosphor manufacturing method, and a white light emitting device. The phosphor is represented as a chemical formula of aMO-bAl2O3-cSi3N4, which uses light having a peak wavelength in a wavelength band of about 350 nm to about 480 nm as an excitation source to emit visible light having a peak wavelength in a wavelength band of about 480 nm to about 680 nm (where M is one kind or two kinds of elements selected from Mg, Ca, Sr, and Ba (0.2≦a/(a+b)≦0.9, 0.05≦b/(b+c)≦0.85, 0.4≦c/(c+a)≦0.9)).