The vast majority (over 90%) of Chinese are Han Chinese. The remainder is distributed among 55 other ethnic groups. This diversity was displayed during the opening ceremonies of the last Olympic games where fifty-six children from the 56 Chinese ethnic groups clustered around the Chinese national flag supposedly represented the 56 ethnic groups. It was later revealed that the children were not actually from those ethnic groups.
Check out this impressive photo gallery that portrays the actual ethnic groups in professionally composed group portraits, with the subjects donning traditional garb and carrying traditional instruments or tools. Pictured above is the ethnic Hui people.