Are there many people in Beijing subway?

A lot. Beijing Subway is one of the busiest subway systems in China. During the morning rush hour and the evening rush hour, the subway cars are very crowded and there is a large flow of people, so passengers need to stand. Some particularly crowded lines and stations, such as 1 line, line 2 and 10 line, are more likely to be congested, especially the stations in the city center.