Russia invaded Ukraine Crimea peninsula, with a well-planned and a surprising method, at low cost and gaining most interests, which is called "Hybrid Warfare." After studing the key factors of Russia's hybrid warfare in Crimea operations, we found that the decisive operation is using special operations forces. The center of gravity lay on civilian population. The connection of using information technology makes hybrid warfare a more serious threat. This essay makes a risk assessment on China threat across the Taiwan Strait with an assumption of using hybrid warfare against Taiwan in order to look for solutions of national security.