In this paper, the MF resin was modified by Benzoguanamine (BG). The effects of different dosage of BG on the molecular structure, tensile strength, elongation at break, resistance to combustion and boiling water resistance were respectively investigated in details. 1H-NMR spectra showed that, after the modification with benzoguanamine, the appearance of new proton signals at 70~76 ppm were attributed to the hydrogen protons of benzene ring. FTIR spectra showed that, after the modification with benzoguanamine, the appearance of 1 557 and 774 cm-1 in BG-MF resins were attributed to the skeleton vibration peak of benzene ring confirmed the success in the synthesis of BG-MF resin. X ray diffraction (XRD) analysis showed that crystal of BG-MF resin had a slight change, this was mainly due to the presence of a large amount of N elements in BG-MF, resulting in the formation of a large number of hydrogen bonds, thereby forming irregular local micro crystals. The DMA test results showed that, the peak storage modulus of MF resin was increased from 17 050 to 20 228 MPa when the BG content reaches 15%, indicating that the bonding strength of BG-MF resin was improved. The tensile strength and toughness of the dipping laminated plate were increased. The elongation at break was increased by 22% at the addition of 15% BG. The oxygen index was increased from 362 to 384, showing that the flame retardancy of BG-MF resin was improved. However, the boiling water resistance of BG-MF resin was not obvious.