The embodiment of the invention discloses a method for receiving random access response information in carrier aggregation. The method comprises the steps that a piece of user equipment (UE) obtains configuration information of a random access response window, enters a random access procedure, continuously monitors physical downlink control channel (PDCCH) scrambled by cell-radio network temporary identifier (C-RNTI) in the random access response window, and receives the random access response (RAR) information from a resource indicated by the PDCCH scrambled by the C-RNTI in the random access response window; when the RAR information is not received successfully in the random access response window, the UE judges whether the transmission times of a random access lead code reaches a maximum transmission times or not, if yes, the UE ends the current random access procedure, otherwise, the UE retransmits the random access lead code to a network side and returns to the steps of continuously monitoring the PDCCH scrambled by the C-RNTI; and the UE receives the RAR information based on a Hybrid Automatic Requestor (HARQ) mechanism. The method disclosed by the invention can determine how to receive the RAR information.