The invention relates to a microsclerotium bacterial strain and a method for biological weed control therewith, belonging to the application of microorganism for agricultural plant protection. The microsclerotium bacterial strain is (SC64) CGMCC with number thereof being NO.2934. The use dosage of weeding bacterial particles obtained by solid fermentation of the bacterial strain ranges from 30g.m-2-150 g.m-2, and the weeding bacterial particles can be applied to poaceae crops such as corn, rice, wheat, barley, sugar cane, kaoliang, millet and poaceae plants such as lawn bermuda grass, zoysia japonica, festuca arundinacea, poa annua, agrostis stolonifera, axonopus compressus, eremochloa ophiuroides, ditch millet to control growth of broad-leaf weed. In addition, in particular, the weeding bacterial particles can be applied to control destructive invasive foreign weeds such as eupatorium adenophorum, solidago canadensis, horseweed herb, conyza sumatrensis, flaveria bidentis, mikania micrantha, annual fleabane herb and fragrant eupatorium herb. 80% of the target weeds can be brought under control, thus having the characteristics of safety and environmental friendliness.