This paper considers the stability of the Korteweg-de Vries solitary wave solution with respect to infinitesmal disturbance.
It is found that the Korteweg-de Vries solitary wave solution is unstable in the Liapunov sense.
Key words Korteweg-de Vries solitary wave solution - unstable - infinitesmal disturbance - Liapunov direct method
Communicated by Chien Wei-zang