I think there are many shopping malls in Beijing, where clothes are cheap and of good quality. Here are some suggestions:

1, Beijing Zoo Clothing Wholesale Market

2. Muxiyuan Bai Rong World Trade Mall

3. Dahongmen Clothing Wholesale Market

4. Beijing Department Store on Wangfujing Street.

In a word, there are many choices to buy clothes in Beijing. You can choose a suitable shopping mall or market according to your own needs and budget.