The invention discloses a 3-substituted oxazole-fused caged dodecaborane compound, a preparation method and application thereof. The structure of the 3-substituted oxazole fused caged dodecaborane compound is as shown in formula (I), and the R 1 Be menthyl or camphoryl; The R 2 for H, C 6‑20 Aryl, C 1‑15 Alkyl, ‑C(O)O‑C 1‑5 Alkyl or ‑C(O)O‑C 6‑20 Aryl, the C 6‑20 Aryl is optionally replaced by 1, 2 or 3 H, F, Cl, Br, I, OH, NH 2 , NO 2 , CN, C 1‑5 Alkyl, C 1‑5 Alkoxy, -O-C(O)-C 1‑5 Alkyl, ‑C(O)‑NH‑C 1‑5 Alkyl, ‑NH‑C(O)‑C 1‑5 Alkyl, ‑C(O)O‑C 1‑5 Alkyl, C 6‑20 Aryl or 5-12 membered heteroaryl substituted; said A + For metal cations, quaternary ammonium cations or phosphorus cations. The preparation method utilizes menthyl and camphoryl as a directing group, selectively activates the 3-position B-H bond, and prepares the compound of formula (I); the stereoselectivity is high, and the yield is good, which increases the chance of discovering new antibacterial drug candidates . The compound of formula (I) provided by the invention has high-efficiency and broad-spectrum antibacterial effects.