Liquid solid two-phase flow, as a complex flow phenomenon, is widely present in various application scenarios of industrial production and daily life This article focuses on the measurement of solid content in liquid-solid two-phase flow. A solid particle concentration measurement device is designed, using an array ultrasonic sensor. The entire ultrasonic phased array testing system is designed, and the corresponding focusing rule is designed to determine the corresponding experimental parameters for scanning through a line scanning probe. Solid tracer particles of different masses were added to the water tank to simulate fluids with different solid content, and different flow rates were set. A total of 140 signal acquisition points were carried out under different operating conditions, and the collected matrices were converted into image information. The gray level co-occurrence matrix method was used to extract features from the images. By analyzing the extracted energy and entropy feature values and the relationship between the concentration and flow rate of solid particles in the two-phase flow, the concentration of solid particles in the water was modeled and fitted. Different ensemble algorithms were used to predict the particle content in the liquid, and the prediction effect was compared the results showed that the light gradient boosting machine (LGBM) model had the best fitting effect, and the intelligent optimization algorithm was used for optimization. The final model fitting accuracy reached 92.85%, providing a new measurement method for measuring the solid content of liquid-solid two-phase flow.