We plan to visit great wall. Do we need a visa for china? we come from united state.

Vivian, how long will you stay in Beijing? If you plan to stay for a week or more, then you need to apply for one in advance before you go. If you just plan to see the wall, then you might make use of 72 hours free transit to visit the wall. In this case, you need to bring your onward air ticket to a third country or region and make sure that your flights won't stop at any other Chinese cities. For example, you can fly from US to Japan but transit in Beijng for less than 72 hours to vsit the wall.