Yes, duty-free shopping for outlying island travelers must meet the following conditions at the same time:
First, having purchased an outlying island ticket and holding a valid identity document, domestic travelers holding a resident identity card (of which Hong Kong, Macao and Taiwan travelers holding a valid travel document), and foreign travelers holding a passport;
Second, having made a payment to purchase duty-free commodities in a designated outlying island duty-free store, with the varieties of commodities and duty-free shopping Secondly, they shall pay for the duty-free commodities in the designated outlying island duty-free shops with the varieties of commodities and duty-free purchases, the amount and quantity of which are within the scope prescribed by the state and obtain the shopping vouchers in accordance with the regulations;
Thirdly, they shall pick up the duty-free commodities they have purchased from the designated pick-up points at the airport isolation area with the identity documents and shopping vouchers and shall take them out of the island on the flights with the passengers.
Expanded Information:
According to the "Announcement on Further Adjustment of Duty-Free Shopping Policies for Hainan's Outlying Island Passengers"
Article 1 The cumulative duty-free shopping limit for outlying island passengers in Sanya (including those who are residents of the island) has been increased to 30,000 yuan per person per year, with no limit on the number of shopping trips.
Article 2 Increase some household medical equipment commodities, add vision training devices, hearing aids, orthopedic fixation devices, household respiratory support equipment (non-life support) to the list of duty-free commodities on the outlying islands, with a limit of two pieces per person per purchase.
Second, in addition to the above adjustments, the other contents of the duty-free policy on the outlying islands continue to implement the "Announcement of the Ministry of Finance on Further Adjustment of Duty-Free Shopping Policies for Hainan's Outlying Island Passengers" (Announcement of the Ministry of Finance of the People's Republic of China*** and the State of China, No. 8 of 2015), "Announcement of the Ministry of Finance on Adjusting the Duty-Free Shopping Policy for Hainan's Outlying Island Passengers" (Announcement of the Ministry of Finance of the People's Republic of China*** and the State of China, No. 73 of 2012 ) and the relevant provisions of the Announcement of the Ministry of Finance on the Pilot of the Duty-Free Shopping Policy for Hainan's Outlying Island Travelers (Announcement of the Ministry of Finance of the People's Republic of China*** and the State of China No. 14 of 2011).
Baidu Wikipedia-Tax Free Policy for Outlying Islands
China.gov.cn-Announcement on Further Adjustment of Duty-Free Shopping Policy for Hainan's Outlying Island Travelers