Discrete integrable systems have received much attention recently because of many applications to numerical algorithms, computer visualization, mathematical physics, etc. The talk will address our recent results of discrete integrable systems; a self-adaptive mesh method of the Camassa-Holm equation and the short pulse equation, ultra-discrete systems (soliton cellular automata), discrete Boussinesq equation. It will be shown that discrete integrable systems will provide very accurate numerical computation methods and a new perspective on integrable systems.