Reform and opening up is a great revolution that the Communist Party of China has led the people of all nationalities in the new era.Over the past 40 years since the Third Plenary Session of the Eleventh Central Committee of the Communist Party of China was convened，our party has been forging ahead and tackling difficulties，and has made remarkable achievements.Since the 18th National Congress of the Communist Party of China，in the face of the new normal in the new era，General Secretary Xi Jinping has stood at the new height of the great rejuvenation of the Chinese nation，carried out in-depth and systematic theoretical thinking，for the realization of the Two Centenary Goal，actively explored and promoted the practice of reform and opening up，and creatively put forward a series of new ideas of reform and opening up.This paper mainly introduces General Secretary Xi Jinping's important discussion on economic，political，cultural，social，ecological civilization and Party building，and deeply studies and comprehends the ideological essence of General Secretary Xi Jinping's reform and opening-up theory，so as to unite closely with the Party Central Committee in which Comrade Xi Jinping is the general secretary，and advance bravely to realize the great rejuvenation of the Chinese nation.