The microscopic properties and physical parameters of the offshore heterogeneous oil reservoirs profoundly change after intensive water injection. The phenomenon of “fluid convergence” of the injected fluid will become prominent, which makes it easy for the development of strongly connected channeling and high-permeability zones between wells. As a result, the injected fluid will experience low-efficiency or even ineffective circulation in the reservoirs. We have established a new method for quickly simulating and predicting the profile control performance in multi-layer oil reservoirs based on the inter-well connectivity. This method has been verified by model analysis with actual oilfield data. Case applications show that this method does not require complicated geological modeling. It overcomes the computational cost of traditional numerical simulation after introduction of profile control, and can increase the calculation speed by at least dozens of times. This method is suitable for guiding the design and application of profile control of large-scale reservoirs.