5 105 15。 According to the official website information of the postcode library, Dayuan area code 020, Baiyun District, Guangzhou City, Guangdong Province. The postal code is 5 105 15. The first two digits of 5 1 represent provinces, municipalities and autonomous regions, the third digit 0 represents postal areas, the fourth digit 5 represents counties and cities, and the last two digits 15 represent specific delivery areas.