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We present an evolutionary population synthesis model of the surfacebrightness fluctuation (SBF) for normal and He-enriched simple stellarpopulations (SSPs). While our SBF model for the normal-He population agreeswith other existing models, the He-rich population, containing hotterhorizontal-branch stars and brighter red-clump stars than the normal-Hepopulation, entails a substantial change in the SBF of SSPs. We show that theSBF magnitudes are affected by He-rich populations at least $\sim$0.3~mag evenin $I$- and near-IR bands at given colors, from which the SBF-based distancesare often derived. Due to uncertainties both in observations and models,however, the SBFs of Galactic globular clusters and early-type galaxies do notallow verifying the He-enriched model. We propose that when combined withindependent metallicity and age indicators such as ${\rm Mg}_2$ and ${\rmH}\beta$, the UV and optical SBFs can readily detect underlying He-richpopulations in unresolved stellar systems at a distance out to $\gtrsim20$\,Mpc. A full set of the spectro-photometric and SBF data for SSPs from theYonsei Evolutionary Population Synthesis (YEPS) model is available for downloadat http://cosmic.yonsei.ac.kr/YEPS.htm.

Yonsei Evolutionary Population Synthesis (YEPS) Model. III. Surface Brightness Fluctuation of Normal and Helium-enhanced Simple Stellar Populations