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<i>Elizabethkingia anophelis</i> has emerged as a critical human pathogen, and a number of isolated reports have described the successful treatment of <i>Elizabethkingia</i> infections with vancomycin, a drug that is typically used to target Gram-positive bacteria. This study employed in vitro broth microdilution checkerboard and time-kill assays, as well as in vivo zebrafish animal models to evaluate the individual and combination antimicrobial effects of vancomycin and rifampin against <i>E. anophelis</i>. The minimum inhibitory concentration ranges of vancomycin and rifampin against 167 isolates of <i>E. anophelis</i> were 16–256 mg/L and 0.06–128 mg/L, respectively. The checkerboard assay results revealed a synergistic effect between vancomycin and rifampin in 16.8% (28/167) of the isolates. Time-kill assays were implemented for 66 isolates, and the two-drug combination had a synergistic interaction in 57 (86.4%) isolates. In vivo zebrafish studies revealed that treatment with vancomycin monotherapy, rifampin monotherapy, or vancomycin–rifampin combination therapy yielded a higher survival rate than the control group treatment with 0.9% saline. The results of this study support the use of vancomycin to treat <i>E. anophelis</i> infections.