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It is well-known that fitting the Color Magnitude Diagrams (CMDs) to thetheoretical isochrones is the main method to determine star cluster ages.However, when the CMDs are not available, the Spectral Energy Distribution(SED)-fitting technique is the only other approach, although it suffers theage-metallicity-reddening degeneracy. In this work, we gather the ages,metallicities and masses of dozens of M31 star clusters from the CMD-fittingwith HST images from the literatures for comparison. We check the reliabilityof the SED-fitting results with different models, i.e., Bruzual \& Charlot 2003model (BC03), Galaxy Evolutionary Synthesis Models ({\sl GALEV}) and AdvancedStellar Population Synthesis (ASPS) for the simple stellar populations (SSPs)with single stars (ss)-SSP/binary star (bs)-SSPs models. The photometry bandsincludes the Galaxy Evolution Explorer {\sl GALEX} FUV/NUV bands,optical/near-infrared $UBVRIJHK$ bands, as well as the Wide-field InfraredSurvey Explorer ({\sl WISE}) $W1$/$W2$ bands. The comparisons show that theSED-fitting ages agree well with the CMD-fitting ages, either with the fixedmetallicity or with the free metallicity for both the BC03 and the {\sl GALEV}model. However, for the ASPS models, it seems that SED-fitting results aresystematic older than the CMD ages, especially for the ages log t <9.0 (yr).The fitting also shows that the {\sl GALEX} FUV/NUV-band are more importantthan the {\sl WISE} $W1$/$W2$ for constraining the ages, which confirms theprevious findings. We also derived the masses of our sample star clusters fromthe BC03 and {\sl GALEV} models and it is found that the values agree well withthat in the literature.

The Ages of M31 Star Clusters: Spectral Energy Distribution Versus Color-Magnitude Diagram