To provide a nonslip device of favorable usability, which is light, compact, and convenient to carry.

The nonslip device 1 comprises an upper hook part 2 with a first hole 2a to be hooked on a shoe tip part, an irregularity surface 3 where pins 3d are provided, and a lower hook part 4 with a second hole 4a to be hooked on a shoe rear end part, which are integrally formed on the surface. The irregularity surface 3 that is roughly oval comprises a first projecting line 3a that is roughly oval formed along the circumference, and a plurality of second projecting lines 3b and roughly circular third projecting lines 3c formed inside the first projecting line 3a. On the holes of the third projecting line 3c, columnar pins 3d are provided to project. On the third projecting line 3c, a fourth projecting line 3e is radially formed from the pin 3d.