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Turbidity of water was a very important parameter in aquaculture. An integrated portable turbidimeter was developed to measure turbidity of water body based on the comprehensive measurement method combined scattering light and transmission light. It used AT89S52 microcontroller as control chip and consisted of the light emission unit, detection unit and control unit. The light emission unit comprised two sets of 860 nm LED light source and the corresponding collimating lens. The detection unit comprised two photoelectric sensors. And the control unit included the light source driving circuit, the two-stage amplification circuit and the A/D conversion circuit. The integrated detector was calibrated in laboratory and carried out field experiments. The results showed that the turbidimeter achieved a high accuracy, the calibration R2c was 0.994 and the validation R2v was 0.999, with the resolution of 0.01 NTU and the error of ± 2%. It was concluded that the turbidimeter reached the practical level.