A quinolonecarboxylic acid derivative represented by the following general formula (I): (wherein R1 is an alkyl group that has 1 to 6 carbon atoms and may or may not be substituted with 1 or 2 or more halogen atoms, a cycloalkyl group that has 3 to 6 carbon atoms and may or may not be substituted with 1 or 2 or more halogen atoms, or an aryl or heteroaryl group that may or may not be substituted with ! or 2 or more substituents that are each independently a halogen atom or an amino group R2 is a hydrogen atom, an alkyl group having\ to 3 carbon atoms, a pharmaceutically acceptable cation, or a functional group acceptable as a prodrug R3 is a hydrogen atom, a halogen atom, a hydroxyl group, an amino group or an alkyl group having 1 to 3 carbon atoms R4 is a hydrogen atom or a halogen atom R5 is a fluorine atom R6 is a hydrogen atom or a fluorine atom and A is a nitrogen atom or =C-X (where X is a hydrogen atom, halogen atom, or alkyl or alkoxyl group that has 1 to 3 carbon atoms and may or may not be substituted with 1 or 2 or more amino groups, cyano groups or halogen atoms.)),and salts and hydrates thereof.
