Abstract: An operation system based on membership level is provided, comprising: a database; a computer device connected to the database, the computer device receiving a member data and setting the member data to a zero-th membership level, the computer device searching in the database for a plurality of (N+1)th-level sub-member data related to the N-th level sub-member data, and setting the (N+1)th-level sub-member data to (N+1)th membership level; and a display device, using the member data as a center, displaying the member data, the first membership level, the second membership level to the (N+1)th membership level, where N being an integer greater than or equal to two. Moreover, an operation method based on membership level is also provided.