Apparatus, system and method for determining transmission power

The invention provides an apparatus, system and method for determining transmission power, which are applied to the field of communications and can improve a frequency spectrum utilization rate. The method for determining transmission power comprises: receiving frequency division information, a first power configuration rule and/or a second power configuration rule sent by a base station; according to the frequency division information, the first power configuration rule and/or the second power configuration rule received by the receiving unit, acquiring a corresponding upper power limit level when the terminal performs data transfer; and according to an upper power limit corresponding to the upper power limit level acquired by the first acquisition unit, acquiring the transmission power when the terminal performs data transfer, wherein the upper power limit represents the maximum transmission power which can be used when the terminal performs data transfer. The apparatus, system and method for determining transmission power provided by the embodiments of the present invention are applied to the determination of antenna transmission power.