A communication device for handling a wireless local area network, WLAN, measurement configuration, the communication device comprising: a storage unit for storing instructions; and a processing means, coupled to the storage unit, wherein the storage unit stores, and the processing means is configured to execute, the instructions of: establishing a connection to a base station, BS, of a cellular network; receiving the WLAN measurement configuration, on the connection, from the BS; performing WLAN measurement on a WLAN according to the WLAN measurement configuration; transmitting a first WLAN measurement result of the WLAN measurement, on the connection to the BS according to the WLAN measurement configuration; receiving a cellular-WLAN aggregation, CWA, configuration, on the connection, from the BS; communicating a plurality of packets with the WLAN according to the CWA configuration; the instructions are further characterised by instructions handling the WLAN measurement configuration when a connection failure occurs: keeping the WLAN measurement configuration, when detecting the connection failure on the WLAN; and releasing the WLAN measurement configuration, when detecting the connection failure on the cellular network. a storage unit for storing instructions; and a processing means, coupled to the storage unit, wherein the storage unit stores, and the processing means is configured to execute, the instructions of: establishing a connection to a base station, BS, of a cellular network; receiving the WLAN measurement configuration, on the connection, from the BS; performing WLAN measurement on a WLAN according to the WLAN measurement configuration; transmitting a first WLAN measurement result of the WLAN measurement, on the connection to the BS according to the WLAN measurement configuration; receiving a cellular-WLAN aggregation, CWA, configuration, on the connection, from the BS; communicating a plurality of packets with the WLAN according to the CWA configuration; the instructions are further characterised by instructions handling the WLAN measurement configuration when a connection failure occurs: keeping the WLAN measurement configuration, when detecting the connection failure on the WLAN; and releasing the WLAN measurement configuration, when detecting the connection failure on the cellular network. establishing a connection to a base station, BS, of a cellular network; receiving the WLAN measurement configuration, on the connection, from the BS; performing WLAN measurement on a WLAN according to the WLAN measurement configuration; transmitting a first WLAN measurement result of the WLAN measurement, on the connection to the BS according to the WLAN measurement configuration; receiving a cellular-WLAN aggregation, CWA, configuration, on the connection, from the BS; communicating a plurality of packets with the WLAN according to the CWA configuration; the instructions are further characterised by instructions handling the WLAN measurement configuration when a connection failure occurs: keeping the WLAN measurement configuration, when detecting the connection failure on the WLAN; and releasing the WLAN measurement configuration, when detecting the connection failure on the cellular network. keeping the WLAN measurement configuration, when detecting the connection failure on the WLAN; and releasing the WLAN measurement configuration, when detecting the connection failure on the cellular network.