The invention relates to a friction driving wheel belt device for a rotary kiln. The friction driving wheel belt device comprises a wheel belt with keys, a plurality of base plate groups arranged at intervals and X-shaped blocks fixed on a barrel of the rotary kiln; each base plate group comprises two convex base plates, the convex ends of the base plates are opposite and are arranged at an interval, and the two base plates are positioned and installed together through a pair of symmetrically arranged X-shaped blocks; two side faces of each base plate are both positioned through baffle plates fixed on the barrel; a pair of wedge blocks for adjusting the circumferential position of the wheel belt with keys is further arranged between the base plate groups; the positions of the wedge blocks are adjusted through a tension device so as to adjust the circumferential position of the wheel belt with keys. The wheel belt with keys of the friction driving wheel belt device is used for transmitting the torque needed by the rotation of the kiln, so that the wheel belt can effectively drive the barrel to operate normally; the inner surface of the wheel belt is made into the type of a square key, and the square key has the advantages of high centering precision and good centering stability.