The present invention is a quadrature RF power detector circuit, which is used in conjunction with a quadrature RF power amplifier to detect and combine RF signals from an in-phase amplifier leg and from a quadrature-phase amplifier leg to provide an RF power detection signal. The quadrature RF power detector circuit includes an emitter follower amplifier for each leg of the quadrature RF power amplifier and may include doubler circuitry to detect both half-cycles of an RF signal. The emitter follower detector provides power detection with minimal DC current and without significant RF loading at the point of detection, such as an RF interstage. This balanced detector also provides more accurate power detection under high VSWR conditions due to the quadrature action minimizing peaks and valleys in the detected voltage.