Abstract: A pipe connector comprises a tubular pin member 1 having a generally frustoconical outer peripheral surface 3 and a tubular box member 2 having a generally frustoconical inner peripheral surface 4 corresponding to the frustoconical outer peripheral surface 3 of the pin member 1 and which overlies the frustoconical surface 4 of the pin member 1 when the members 1, 2 are fully engaged together. A circumferentially extending groove 14, 15 is formed in each of the pin member 1 and the box member 2 at the root end of the frustoconical surface 3, 4 thereof, and a nib 12, 13 is formed on the tip of each of the pin 1 and box 2 members such that, upon full engagement of the pin 1 and box 2 members, the nibs 12, 13 of the pin 1 and box 2 members engaging respectively in the grooves 14, 15 of the box 2 and pin 1 members so as to radially restrain the free ends of the pin 1 and box 2 members.