Abstract: The standard cipoletti weir and its flow measurement formula were improved aiming at some problems, which existed in the flow measurement of irrigation area. Experimental research of the improved cipoletti weir was carried out. According to the indoor experiments and the analysis of flow measurement formula of the standard cipoletti weir, the flow measurement formula of the improved cipoletti weir was put forward. At the same time, the flow measurement precision and prototype observation experiment were analyzed. The results indicated that flow measurement method and calculation precision were consistent with the rule of country agricultural flow rate measurement, which could be used in the field channel to measure the flow.