During horizontal well production operations, maintaining fluid flow within the wellbore necessitates a specific pressure gradient. Accurate characterization of this pressure drop is critical for elucidating the seepage dynamics in horizontal wells. This study focuses on a horizontal well section in a designated oilfield to investigate the flow behavior of perforated-completion horizontal wells. The workflow includes: (1) delineating distinctions between horizontal wellbore fluid flow and conventional tubular flow regimes; (2) formulating a wellbore pressure drop model that accounts for hydraulic resistance encountered during fluid migration; (3) analyzing pressure drop patterns by integrating the perforation-completion pressure loss model with reservoir lithological constraints and operational parameters; (4) implementing a calibration factor to dynamically adjust wall friction coefficients, enabling equivalent corrections for wellbore diameter anomalies or surface roughness variations. This methodology achieves high-fidelity equivalence in reservoir simulation workflows, significantly improving predictive accuracy in horizontal well performance modeling.