8:30. According to the query Dongguan local treasure know, Dongguan invoice morning 8:30 open. Dongguan tax office hours, Monday to Friday (8:30 am - 12:00 pm, 14:00 pm - 17:30), except for legal holidays. Dongguan, prefecture-level city under the jurisdiction of Guangdong Province, megacity, Dongguan is located in South China, south-central Guangdong Province, the east bank of the Pearl River Estuary, northwest of Guangzhou City, south of Shenzhen City, northeast of Huizhou City, the city's land area of 2,460 square meters.