The result of "US's war on Iraq" not only affects mid-east Asia and global strategic structure but also vibrates China's military preparation, as which viewed as US' potential enemy. "Every battle waged by U.S force may help to reduce the gap between the PLA (People's Liberation Army)," as PLA has believed and taken as its own experience to modify the military establishment. Under the experience of hi-tech and advanced war such as War on Iraq and Kosovo, I intend to explore on what the PLA learned and did after the war on Kosovo. In the meantime, I will examine the observation and evaluation of the PLA on this war and predict the influence of War on Iraq for PLA's development and the trends of war preparation. Finally I will assess PLA's learnings from the War on Iraq, and the relating influence for Asian Pacific security affairs. There are some viewpoints mentioned in this paper, such as defense budget increment, over-limit warfare capability, the experience reflecting on "countering the U.S. and attacking Taiwan", the revolution in military affairs, etc. The event of War on Iraq has already arisen PLA's determination to reach modernization, and the PLA's behavior has also alerted China's neighbor countries. The argument about "China, the coming threat" has also been to reinforced.