The invention concerns a mark (3; 31; 32; 33; 34; 35) for pairing a pair of socks (1, 2; 10, 20; 30, 40; 50, 60; 70, 80; 90, 100). It consists of a portion of fabric, combined with each sock of the pair of socks, having the same colour for each sock of the pair of socks, but different from the colour constituting the background of the pair of socks. The invention also concerns pairs of socks provided with said mark.