Abstract: In order to analyze the effect of ration parameter on surface properties of fiber asphalt macadam. The direct drawing and torsional sheer test were used to test strength on molding specimens which was on the basis of material composition and mechanical properties of fiber asphalt macadam. The orthogonal analysis method was used to analyze experimental results and the effect law of ration was drawn. The research shows that the influence of amount of emulsified asphalt and gravel content on fiber asphalt macadam surface strength is more significant than that of fire content and length. The tensile strength of the interlayer increases gradually with the increasing amount of emulsified asphalt and gravel.The shear strength increases with the increasing amount of emulsified while increases first and then decreases with the growth of gravel content. At last,when the amount of emulsified asphalt is 2. 0 kg / m2,stone dosage is 13 kg / m2,fiber is 0. 1 kg /m2 and fiber length is 60 mm,the surface performance is optimal.