tsim.in, Buying China SIM cards in China is difficult for travelers due to language barriers, national roaming charges, the lack of International calling on most cards and the sometimes high cost to call India. Beware also of the occasional scams!
General Availability
Most Chinese SIM cards are regional, which means if you travel to a different province you’ll pay higher rates, so try to buy a SIM card in the province where you’ll be spending the most time. SIM card information related to Beijing will be discussed below.
SIM Cards are sold everywhere in Beijing. You can buy a SIM card right at the airport. Alternatively, they are available in departmental stores, bookstores, post office, and sometimes on the street. The value of the card is stated clearly on the card, and that’s how much they sell it for. You might get a SIM card from a retail store on street, but you still have to go to the service point of the carrier for official registration and activation before using it.