A communication device of handling uplink, UL, power control, the communication device comprising: a storage unit; and a processing means, coupled to the storage unit, wherein the storage unit stores instructions, and the processing means is configured to execute the instructions of: determining that a first UL transmission on a first serving cell of a network and a second UL transmission on a second serving cell of the network are overlapped; keeping a transmission power level of the first UL transmission and adjusting a first transmission power level of the second UL transmission to a second transmission power level of the second UL transmission, according to a power level limit of the communication device, if a sum of the transmission power level of the first UL transmission and the first transmission power level of the second UL transmission is greater than the power level limit; performing the first UL transmission according to the transmission power level of the first UL transmission; and performing the second UL transmission according to the second transmission power level of the second UL transmission; wherein the first serving cell is a licensed serving cell, and the second serving cell is an unlicensed serving cell; wherein the second transmission power level of the second UL transmission is greater than a minimum transmission power level of the second UL transmission. a storage unit; and a processing means, coupled to the storage unit, wherein the storage unit stores instructions, and the processing means is configured to execute the instructions of: determining that a first UL transmission on a first serving cell of a network and a second UL transmission on a second serving cell of the network are overlapped; keeping a transmission power level of the first UL transmission and adjusting a first transmission power level of the second UL transmission to a second transmission power level of the second UL transmission, according to a power level limit of the communication device, if a sum of the transmission power level of the first UL transmission and the first transmission power level of the second UL transmission is greater than the power level limit; performing the first UL transmission according to the transmission power level of the first UL transmission; and performing the second UL transmission according to the second transmission power level of the second UL transmission; wherein the first serving cell is a licensed serving cell, and the second serving cell is an unlicensed serving cell; wherein the second transmission power level of the second UL transmission is greater than a minimum transmission power level of the second UL transmission. determining that a first UL transmission on a first serving cell of a network and a second UL transmission on a second serving cell of the network are overlapped; keeping a transmission power level of the first UL transmission and adjusting a first transmission power level of the second UL transmission to a second transmission power level of the second UL transmission, according to a power level limit of the communication device, if a sum of the transmission power level of the first UL transmission and the first transmission power level of the second UL transmission is greater than the power level limit; performing the first UL transmission according to the transmission power level of the first UL transmission; and performing the second UL transmission according to the second transmission power level of the second UL transmission; wherein the first serving cell is a licensed serving cell, and the second serving cell is an unlicensed serving cell; wherein the second transmission power level of the second UL transmission is greater than a minimum transmission power level of the second UL transmission.