Disclosed is a novel oxazolidinone derivative represented by Formula 1 above, in particular, a novel oxazolidinone compound having a cyclic amidoxime or cyclic amidrazone group.In Formula 1, R and Q are the same as defined in the detailed description.In addition, disclosed is a pharmaceutical composition for an antibiotic which includes the novel oxazolidinone derivative of Formula 1, a prodrug thereof, a hydrate thereof, a solvate thereof, an isomer thereof, or a pharmaceutically acceptable salt thereof as an active ingredient.The novel oxazolidinone derivative, the prodrug thereof, the hydrate thereof, the solvate thereof, the isomer thereof, and the pharmaceutically acceptable salt thereof have broad antibacterial spectrum against resistant bacteria, low toxicity and strong antibacterial effects against Gram-positive and Gram-negative bacteria and thus may be effectively used as antibiotics.