In a communication system in which a base station apparatus and a terminal apparatus communicate with each other, a base station apparatus, a terminal apparatus, and a communication system with which the base station apparatus and the terminal apparatus can efficiently communicate with each other are provided. The terminal apparatus that communicates with the base station apparatus includes a radio resource control section 6011 that sets a first uplink power control-related parameter configuration and a second uplink power control-related parameter configuration in accordance with information included in a radio resource control (RRC) signal, a reception unit 605 that determines a type of downlink control information (DCI) format, a transmission power control section 6015 that sets uplink transmission power on the basis of the first uplink power control-related parameter configuration or the second uplink power control-related parameter configuration, and a transmission unit 607 that transmits an uplink signal with the set uplink transmission power.