Provided are a nanophosphor and a silica composite including the nanophosphor. The nanophosphor has a core/first shell/second shell structure or a core/first shell/second shell/third shell structure, wherein the core includes a Yb3+-doped fluoride-based nanoparticle, the first shell is an up-conversion shell including a Yb3+ and Tm3+-codoped fluoride-based crystalline composition, the second shell is a fluoride-based emission shell, and the third shell is an outermost crystalline shell.