The present disclosure provides a method for predicting a water invasion frontier for a complex well in a bottom-water gas reservoir. The technical solution is as follows: with consideration of forms of different well types and a gravitational pressure drop in production, a coupled permeability of a corresponding well type acting on a gas-water interface under the action of a baffle plate is expressed by using an equivalent percolation resistance method; a productivity of each infinitesimal section of the corresponding well type is calculated; a position of the gas-water interface is calculated with an equivalent permeability and a pseudo-productivity as characteristic parameters; water breakthrough is determined when there is a point over a water avoidance height, and a change in water invasion frontier form may be expressed with water quality point position data at this time.