The present invention discloses a method for transmitting uplink control channel, a device and a system thereof. In the solution of the invention, after the CCE index and UE corresponding with the first CCE of PDCCH corresponding to the PDSCH resource allocation transmit the PUCCH resource index implicit mapping of PUCCH resource of HARQ-ACK package information, the RB indexes of resource block RB of PUCCH resource which transmits HARQ-ACK package information between two different time slots are respectively RB1,k and RB2,k, k, wherein k is selected from the range from 0 to N-1, and wherein N is the number of carrier component comprising PDSCH. The HARQ-ACK package information is transmitted selectively in the PUCCH resource corresponding with PDSCH on the K'-th carrier component, and k' satisfies the following relationship: k'=arg max(Metric(k)), wherein Metric(k)=abs(RB1,k-RB2,k). The PUCCH resource index of PUCCH resource is nPUCCH, k'. The maximum of RB index difference value means the maximum span length of frequency resource corresponding with two time slots on the frequency domain, thereby a larger frequency diversity gain can be obtained thereby enhancing the transmission efficiency of PUCCH and the transmission quality of whole transmission system is increased.