Disclosed is a flexible-circuit flat cable with cluster section, including at least one cluster section, at least one slip section, a first connection section, and a second connection section. The first connection section is set at a first end of the cluster section. The slip section has a first end connected to a second end of the cluster section and a second end at which the second connection section is set. The four sections are all provided with a plurality of signal transmission lines corresponding to and connecting each other. The first connection section and the second connection section are selectively provided with a connector or a plugging end. Further, the cluster section includes a cluster structure composed of a plurality of clustered flat cable components that are formed by slitting in a direction parallel to extension direction of a flexible circuit board to impose free and independent flexibility for bending to each clustered flat cable component.