In order to realize the aim of controlling multiple microscreen drum filters with frame in recirculating aquaculture systems wastewater treatment processing, manage and maintain the system conveniently as well as save production costs, three kinds of operation modes control programs of ten microscreen drum filters were programmed with STEP 7 MicroWIN SP9 V4.0 software. The results of PLC real-time monitoring and debugging showed that the operation modes of the control system could be switched freely, and the microscreen drum filters could work normally in manual mode, automatic mode and timing mode. More concretely, taking one of the filters as an example, for manual mode, the backwashing can be controlled and stopped at any time;for automatic mode, the start and stop of the reducer and the backwashing pump were controlled by two level switches, when they were triggered by the water in the drum, the backwashing was performed, when the water level was dropped below the low level switch, backwashing would stop, and if the switches had malfunctions, backwashing would not proceed;for timing mode, the backwashing time and frequency can be set according to the water quality. In aquaculture environment, the use of multi-mode soft logic control system to make multiple microscreen drum filters’ reducers and backwashing pumps run and stop had the advantages of good stability, high degree of automation and low costs compared with the traditional hard logic control system which went wrong easily and was difficult to be overhauled, and the former can better cope with the problems of system failure. The research results can provide some references for the further improvements of control system of the microscreen drum filters and the automation integration of aquaculture equipments.