a complex circuit board including a printed circuit board assembly and a flexible printed circuit for providing driving signals for light sources is disclosed . the pcba includes a supporting portion and a connecting portion . the light sources are disposed above the supporting portion . the connection portion contacts electrically with a contacting portion of the fpc . the contacting portion of the fpc has a fixing hole . the connecting portion of the pcba has a fixing portion . moreover , the fpc has two or more than two first bend portions on the contacting portion . the fixing portion of the pcba is inserted into the fixing hole of the fpc to complete the complex circuit board without extra attachment units . therefore , the assembly procedure is simplified to increase throughput and the cost is reduced .