To provide a distinction data writing apparatus writing on a memory means of an IC chip in a golf ball by establishing a secure electromagnetic coupling with a communication coil and a resonance coil enclosed in the ball.

This distinction data writing apparatus has the golf ball guiding member 17 which is fixed in a tilted angle, a communication control means which has a communication coil 19 located on the lower face of the guiding member and sends and receives signals by an electromagnetic coupling with a resonance coil enclosed in the ball 2, a braking member 28 which brakes the ball 2 rolling along a path 16 at the writing position facing the communication coil 19, a rolling control means which moves the braking member 28 reciprocatively in a predetermined range and rolls the ball 2 and a writing control means. The writing control means carries out sequentially the data writing process, the data reading process, and the data collating process. If the distinction data is not written correctly, the ball rolling process and the data-rewriting process are carried out.