An exhaust filter system, adapted for removing substances entrained in an exhaust gas from a nonroad engine, includes a casing having a filter cavity for communicating with an exhaust outlet of the generator and a filter core which includes a plurality of filtering loops, each having a plurality of air pores, coaxially received in the filter cavity, a plurality of filtering spacers each having a plurality of air meshes and positioned between each two filtering loops to define a plurality of air passages therebetween, and a catalyzing element for chemically reacting with the substances of the exhaust gas. Therefore, when the exhaust gas passes through the air passages of the filter core, the exhaust gas is evenly diffused to the filter cavity through the air pores and the air meshes so as to enhance a chemical reaction of the exhaust gas with the catalyzing element.