Surface-coated phosphor particle, method for producing surface-coated phosphor particle, and light emitting device

A surface-coated phosphor particle of the present invention includes a particle containing a phosphor and a coating portion that coats the surface of the particle, wherein the phosphor has a composition represented by the general formula M1aM2bM3cAl3N4-dOd (wherein M1 is one or more elements selected from the group consisting of Sr, Mg, Ca, and Ba, M2 is one or more elements selected from the group consisting of Li and Na, and M3 is one or more elements selected from the group consisting of Eu and Ce), in which the values for a, b, c, and d satisfy each of the following formulas: 0.850 ≤ a ≤ 1.150, 0.850 ≤ b ≤ 1.150, 0.001 ≤ c ≤ 0.015, 0 ≤ d ≤ 0.40, 0 ≤ d/(a+d) < 0.30, the elemental fluorine content is at least 15% by mass but not more than 30% by mass of the entire surface-coated phosphor particle, and the rate of mass increase obtained by measurement under prescribed conditions is 15% or less.