In ancient China, New Year's Day (Yuan Dan in Chinese Pinyin) has been referred to the first day of the lunar calendar. Chinese character "Yuan" means "the beginning", Chinese character "Dan" means "day, so "Yuan Dan" collectively means "the initial day", i.e., the first day of a year.
On September 27, 1949, the First Plenary Session of the Chinese People's Political Consultative Conference made the resolution that People's Republic of China would adopt AD chronology for chronological record of events. To distinguish between the two new years in lunar and Gregorian calendars, given that "Beginning of Spring", one of the lunar twenty-four solar terms comes around the lunar new year, the first day of lunar January is renamed as the "Spring Festival", while the first day of the first solar month is called "New Year's Day", thus the two new years become festivals spent by the whole nation.