THE PRESENT INVENTION IS TO PROVIDE AN OXOPYRAZINE DERIVATIVE HAVING AN EXCELLENT HERBICIDAL ACTIVITY AND BESIDES EXHIBITING HIGH SAFETY FOR USEFUL CROPS AND THE LIKE, OR A SALT THEREOF, AND A HERBICIDE CONTAINING THE SAME. THE PRESENT INVENTION RELATES TO AN OXOPYRAZINE DERIVATIVE REPRESENTED BY FORMULA [I]: [CHEMICAL FORMULA 39] WHEREIN X1 REPRESENTS AN OXYGEN ATOM OR A SULFUR ATOM； X2 REPRESENTS CH OR N(O)M； M REPRESENTS AN INTEGER OF 0 OR 1； R1 REPRESENTS A HYDROGEN ATOM, A C1-C12 ALKYL GROUP AND THE LIKE； R2 REPRESENTS A HALOGEN ATOM, A CYANO GROUP AND THE LIKE； R3 IS A HYDROXYL GROUP, A HALOGEN ATOM AND THE LIKE； A1 REPRESENTS C(R4R5)； A2 REPRESENTS C(R6R7) OR C=0； A3 REPRESENTS C(R8R9)； R4 TO R9 REPRESENT A HYDROGEN ATOM OR AN ALKYL GROUP, OR A SALT THEREOF, AND A HERBICIDE CONTAINING THESE COMPOUNDS.
