Method for improving recovery ratio of fractured bottom water gas reservoir through drainage of low part of horizontal well

The invention discloses a method for improving the recovery ratio of a fractured bottom water gas reservoir through drainage of a low part of a horizontal well, and the method comprises the following steps: S1, dividing a bottom water breakthrough area of a target fractured bottom water gas reservoir, and delineating a favorable development area of the target fractured bottom water gas reservoir in the bottom water breakthrough area; s2, determining a high gas saturation horizon and a gas-water interface position of the target fractured bottom water gas reservoir; s3, acquiring actual production data of a target fractured bottom water gas reservoir, and determining a production vertical well in which the target fractured bottom water gas reservoir is completely flooded to stop production according to the actual production data; and S4, according to the favorable development area, the high-gas-saturation horizon and the gas-water interface position, a horizontal well is dug through a shaft of the production ve