Provided are a method for early data transmission. According to an embodiment of the present disclosure, the method includes transmitting a radio resource control (RRC) connection resume request message to a control plane (CP) of central unit (CU) of the network node, receiving information informing that downlink (DL) data exists from the CP, receiving DL data from a user plane (UP) of the CU, transmitting the DL data to a wireless device in response to the information, upon receiving the DL data, and releasing transmission resources after transmitting the DL data.