To provide a string for a racket having a high ball hitting durability and a long service life.

This string comprises a core thread 1,a plurality of side threads 2 and 3 spirally wound about the core thread 1, and a coated layer 4 made of synthetic resin coated about the side threads 2 and 3. A fiber containing organopolysiloxane is used for at least part (side thread 3 in the drawing) of the core thread 1 or the side threads 2 and 3.