The present invention is to provide an oxopyrazinederivative having an excellent herbicidal activity and besidesexhibiting high safety for useful crops and the like , or a saltthereof, and a herbicide containing the same.The present invention relates to an oxopyrazine derivativerepresented by formula [I]:[Chemical Formula 39](see formula I)wherein X1 represents an oxygen atom or a sulfur atom； X2represents CH or N(O)m； m represents an integer of 0 or 1； R1represents a hydrogen atom, a C1-C12 alkyl group and the like；R2 represents a halogen atom, a cyano group and the like； R3is a hydroxyl group, a halogen atom and the like； A1 representsC(R4R5)； A2 represents C(R6R7) or C=O； A3 represents C(R8R9) ； R4to R9 represent a hydrogen atom or an alkyl group,or a salt thereof, and a herbicide containing thesecompounds.
