[Problem to be Solved]Provided is a red emitting fluorescent material, which has a large excitation band and which is capable of efficiently emitting red fluorescence when excited by light emitted from an ultraviolet light emitting device and a blue light emitting device serving as an excitation source, in particular, even by use of an ultraviolet LED having an emission peak at near 390 nm to 400 nm, and which is capable of emitting red fluorescence when excited not only by ultraviolet and blue light from an ultraviolet light emitting device and a blue light emitting device but also by fluorescence emitted from a fluorescent material upon receipt these light beams, thereby emitting high brightness red light, and then, provided is a white light emitting device capable of emitting white light having excellent color reproducing and rendering properties.[Solution]The red emitting nitride fluorescent material of the present invention is represented by Formula (1): Sr1-xAlSi4N7:Eux  (1) where x is a numerical value of greater than 0 to less than 1.