Provided are a flexible circuit mother board and a detection method. The flexible circuit mother board includes flexible circuit daughter boards, at least one detection terminal group and external pad groups corresponding to the flexible circuit daughter boards in one-to-one correspondence. Each flexible circuit daughter board has a bonding pad area adjacent to a corresponding one of the plurality of external pad groups. Each detection terminal group detects at least one flexible circuit daughter board, and each of the at least one detection terminal group comprises a plurality of detection terminals. Each flexible circuit daughter board includes a plurality of capacitors including a first electrode plate and a second electrode plate. Each of the first electrode plate and the second electrode plate is electrically connected to one detection terminal.