Hotels generally provide wall  outlets in every room. China uses a 220 volt power supply for standard domestic and business purposes.

To avoid damage to your device, please follow these guidelines:

(1) Read the label on your device first, if it specifies only "120 volts" (USA and Japan), do not plug it in. 

(2) Avoid turning the power on and off from a wall switch while your device is plugged in.

(3) Use a surge-protector with your laptop, especially if it is an older model. 

(4) Please ensure the plug is firmly inserted in the outlet,

(5) Please do not allow children to plug or unplug devices.

Many electrical outlets are versatile, accommodating many types of  electrical plugs. Exercise care in your use of electrical outlets. Your  electrical device may have a plug that fits in the electrical outlet,  but your device may be damaged by the electricity if it is not designed  to use 220 volts.

New laptop computers and new mobile phone chargers from the larger  manufacturers are likely to be able to work with Chinese electrical  outlets. If you can not use your mobile phone charger you can probably  buy one (likely less than 50 RMB) at a local mobile phone store.

Because our outlets can accommodate so many types of plugs, care must  be exercised when inserting the plug in the outlet to ensure the  contacts are firmly in place. Straight two-pin rectangular (US and Japan  style) and cylindrical plugs (German and European style) and triangular  3-pin plugs (heavy-duty appliance style) can be used.