Abstract: Boundary layer is separated for the barrier along the flow border line, thus the circumfluence is strengthened and the flow pattern deteriorated. Using the method of sucking spouting water, namely, sucking part of the discharge in the upstream of the convex barrier and spouting it downstream, can reduce the intensity and size of circumfluence. The results of flume tests show that a suitable sucking spouting discharge (1 5%-2% of the whole discharge) can cut the length of the circumfluence down to 20%-30%.