A communication device for handling uplink power control configured to communicate with a first base station and a second base station, comprising: a storage unit for storing instructions; and a processing means, coupled to the storage unit, wherein the storage unit sores, and the processing means is configured to execute the instructions of: determining a power level of a first uplink, UL, subframe of the first base station and a first power level of a second UL subframe of the second base station according to an initial power level of the first UL subframe and an initial power level of the second UL subframe, wherein a starting boundary of the second UL subframe is within the first UL subframe; performing a first UL transmission with the first base station in the first UL subframe according to the power level of the first UL subframe; determining a second power level of the second UL subframe of the second base station and a first power level of a third UL subframe of the first base station according to the first power level of the second UL subframe and an initial power level of the third UL subframe, wherein a starting boundary of the third UL subframe is within the second UL subframe; and performing a second UL transmission with the second base station in the second UL subframe according to the second power level of the second UL subframe. a storage unit for storing instructions; and a processing means, coupled to the storage unit, wherein the storage unit sores, and the processing means is configured to execute the instructions of: determining a power level of a first uplink, UL, subframe of the first base station and a first power level of a second UL subframe of the second base station according to an initial power level of the first UL subframe and an initial power level of the second UL subframe, wherein a starting boundary of the second UL subframe is within the first UL subframe; performing a first UL transmission with the first base station in the first UL subframe according to the power level of the first UL subframe; determining a second power level of the second UL subframe of the second base station and a first power level of a third UL subframe of the first base station according to the first power level of the second UL subframe and an initial power level of the third UL subframe, wherein a starting boundary of the third UL subframe is within the second UL subframe; and performing a second UL transmission with the second base station in the second UL subframe according to the second power level of the second UL subframe. determining a power level of a first uplink, UL, subframe of the first base station and a first power level of a second UL subframe of the second base station according to an initial power level of the first UL subframe and an initial power level of the second UL subframe, wherein a starting boundary of the second UL subframe is within the first UL subframe; performing a first UL transmission with the first base station in the first UL subframe according to the power level of the first UL subframe; determining a second power level of the second UL subframe of the second base station and a first power level of a third UL subframe of the first base station according to the first power level of the second UL subframe and an initial power level of the third UL subframe, wherein a starting boundary of the third UL subframe is within the second UL subframe; and performing a second UL transmission with the second base station in the second UL subframe according to the second power level of the second UL subframe.