Flow rate measurement in multiphase flow is essential for process control and safety production. As the drawbacks of conventional flowmeter measurement error produced by the heterogeneous phase or velocity distribution, a measurement technique combining an electrical resistance tomography (ERT) and an ultrasound Doppler (UD) sensor is proposed. The UD sensor obtains the dispersed particle velocity distribution, and the ERT acquires the solid-phase distribution. An experimental platform is constructed for the liquid–solid two-phase horizontal flow experiments. The dual-plane ERT with the cross correlation signal analysis compensates for the inaccurate particle velocity measurement at the bottom of the pipe by using UD independently due to the locally high concentration. The liquid–solid two-phase mixed flow rate under different flow regimes is measured with the two sensors. The proposed method has a 6.3% maximum uncertainty for the liquid–solid two-phase flow rate measurement.