Automobile filter paper can be used as the filtering medium of the automobile filter. As the resin-impregnation process is usually industrially applied, emulsion is required during the manufacturing process of automobile filter. In addition to such critical properties as air permeability (porosity) and water resistance, good strength properties are always necessary. However, the influence of emulsifiers used for the preparation of automobile paper on the strength properties of paper has been rarely reported. In this work, using the preemulsification and semicontinuous copolymerization method, a series of styrene-acrylic emulsions were prepared, which were subsequently used for the preparation of emulsion-impregnated automobile filter papers. The parameters including emulsion dosage, drying temperature, and drying time were controlled at 20%, 140 degrees C, and 6 min, respectively. The influence of emulsifiers on tensile and burst properties, and stiffness of the filter paper was investigated. The use of emulsifiers contributed significantly to paper strength. When the emulsifiers including OP-10/DSB, OP-10/COPS-1,0R-2/DSB, FOR-3/DSB, FOR-3/S-100, FOR-3/COPS-1, and FOR-3/RE-610 were used, tensile strength of above 3.15 KN.m-1 was achieved. When the emulsifiers including OP-10/SDS,OP-10/FR-1, OR-2/DSB, OR-2/SR-10,0R-2/C0-436,0R-2/0E-40,S-201/DSB,S -201/SR-10,S-201/FR-1,FOR-3/S-100,FOR-3/COPS-1, and FOR-3/RE-610 were used, paper stiffness was maintained at above 3.45 mN.m. When the emulsifiers including OP-10/DSB, OP-10/S-100, OP-10/SR-10, OP-10/FR-1,0P-10/RS-610,0R-2/SDS,OR-2/DSB4OR -2/0E-40,S-201/COPS-1,S-201/RE-610,S-201/RS-610, FOR-3/DSB, and FOR-3/RE-610 were used, the burst strength was maintained at above 250kPa. On balance, the emulsifiers capable of maintaining good paper strength (i.e., tensile strength of above 3.15 KN.m-1, stiffness of above 3.45 mN.m, and burst strength of above 250kPa) were OP-10/FR-1, OR-2/DSB, S-201/DSB, S-201/SR-10, S-201/FR-1, and FOR-3/RE-610.