Abstract The September 3, 2011 is the 66th anniversary of the victory of the Second Sino-Japanese War. In the Last year's anniversary, Hu Jintao, the leader of the mainland China, made a speech while visiting the Marco Polo Bridge where the war broke out. In the speech, he changed the tone used in the 60th anniversary, and denied the contribution which the KMT Army had made during the war. Then, he put all the credit to the Chinese Communist Party (CCP), saying that the CCP was the core power of national salvation and liberation at then. Moreover, the People's Daily also pointed out that it was the CCP which stood out first and launched counterstrike to the intruders. The thesis was written to unveil the history distorted by CCP. Based on it, there are several issues below need to be discussed. First of all, how the CCP grew into a millions of regulararmy from a small rebel group? Secondly, how was the relationship between the two parties? Further, what had they done to uphold their political ideas during the war? Through studying the issues above, The thesis is trying to provide reflection and awareness about the relationship between the ROC and PRC. This thesis affirms that the Communist forces did have certain contribution in its efforts to fight behind enemy lines, to mobilize the masses, and to carry out guerrilla warfare. Even so, it cannot be replaced that the contributions which the KMT army made in the main battlefield during the war. Therefore, our people should understand the truth of the history and defend it to honor and remember those martyrs who had fought for our nation with their heroic and glorious deeds.