Abstract: The aluminum salt of methylethylphosphinate (Al(MEP)) was used as a flame retardant filler for EP, Al(MEP)/EP composites with different composition were prepared. The flame retardancy was investigated with limited oxygen index (LOI) and UL 94 vertical burning test. The structure, thermal stability, glass transition temoerature (T_g) and morphology of the samples were characterized by Fourier transform infrared analysis (FTIR), TG analysis, DSC and SEM, respectively. The flexural and impact properties of the composites were also investigated. Results show that Al(MEP)/EP composite with only 15% mass fraction of Al (MEP) can achieve the optimal flame retardancy with LOI value of 32.5% and UL 94 V-0 rating. The evaluation indicats that Al(MEP)/EP composites have good thermal and mechanical properties.