The present invention discloses a power control method, apparatus, and system. The power control method of the present invention includes: when a service runs in a first-standard communication system, determining a transmit power P1 of the first-standard communication system; determining that the transmit power P1 is higher than or equal to a threshold value P2 of power interference of the first-standard communication system to a second-standard communication system; use a power lower than P1 to send data on an interference frequency of the first-standard communication system. According to the power control method in the present invention, a signal transmit power of the interfering frequency of the first-standard communication system can be reduced when it is determined that the first-standard communication system will cause interference to the second-standard communication system, thereby reducing the interference of the first-standard communication system to the second-standard communication system.