To obtain the subject composition, exhibiting excellent braking property on frozen road or on snowy road without damaging the road surface, and good in processability, dispersibility and durability by blending a tread rubber component with a synthetic fiber having specific diameter and specific fiber length and treated with an adhesive in a specific amount.

This composition is obtained by blending (A) 100 pts.wt. rubber component containing a natural rubber and a diene-based synthetic rubber as main components [e.g. a rubber component prepared by blending 100 pts.wt. blend rubber consisting of 50-80 pts.wt. natural rubber and 20 50 pts.wt. polybutadiene rubber with 40-85 pts.wt. carbon black, if necessary, further, 10-30 pts.wt. hydrophilic inorganic reinforcing agent such as white carbon or silane modified clay] with (B) 3-20 pts.wt. synthetic fiber treated with an adhesive treating liquid comprising a resorcine-formaldehyde latex, etc., having 150-400μm diameter and 2-10mm fiber length (e.g. polyamide, polyester or polyvinyl alcohol).