The Chinese telegraph office had played an important role in the time of Chinese modernization movement. At the beginning of building the telegraph office, it is obviously in order to meet the military affairs' requirement firstly, but in the academia, few scholars focus on the function of the telegraph office in the war. But after Sino-Japanese War of 1894, both the Chinese Army and Navy were terribly defeated. The terrible defeat of China was not resulted from the Chinese weapons or commandments, but from the backward political system and the widespread corruption in the government of Qing dynasty. This article is trying to discuss the effect of the telegraph office in the time of China-Japan War of 1894 roundly by considering the relation between the both sides.