Jiaomen outlet is a typical river network bifurcated estuary and an important channel for flood discharge and sediment discharge of the Zhujiang River. The change of diversion ratio in bifurcated Jiaomen outlet is crucial to the geomorphological evolution, flood control and navigation safety of the Zhujiang River Delta. This study designed a series of flume experiments, and selected sensitivity analysis parameter which includes the water depth of bifurcated channel and bifurcated angle to explores the evolution of the flow division ratio of the river network type bifurcated estuary with the above factors. The dimension of the physical model is based on the recent geomorphic morphology of Jiaomen outlet. The result show that, on the basis of the stability of the section feature of the bifurcated channel, the flow division ratio of Fuzhou Channel depicts a good correlation with the flow velocity ratio between Humen and Jiaomen, and is less affected by the absolute flow velocity of the two outlets. Subsequently, the sensitivity experiment result indicate that the flow division ratio is negatively correlated with the water depth of Jiaomen South Channel and positively correlated with the water depth of Fuzhou Channel, and when the bifurcation angle is between 30° and 65°, the flow division ratio is negatively correlated with the bifurcation angle, but when the bifurcation angle is between 65° and 75°, the positive and negative correlation between the flow division ratio and the bifurcation angle changes around the velocity ratio V = 0.7. Then, the sensitivity of the increase or decrease of the flow division ratio to the above each variable can be obtained by quantifying the sensitivity experiment result. The research results can provide reference for artificial regulation project of Jiaomen outlet.