To reduce energy consumption and enhance waste heat recovery efficiency in natural gas heat treatment furnaces, research was conducted based on the numerical simulation software Fluent to investigate the convective condensation coupling heat transfer process in twisted honeycomb tube heat exchangers. The research systematically examined thermal and flow resistance characteristics under various operational conditions and boundary configurations while exploring its underlying heat transfer mechanisms. The results reveal that the proposed configuration effectively reduces flue gas temperature from 950 ℃ to 260 ℃. Optimal performance occurs when auxiliary combustion gas and flue gas velocities reach 0.035 m/s and 0.030 m/s respectively, achieving 96% heat transfer enhancement and 41% improvement in average heat transfer coefficient. An increase in controlled Reynolds number (Re) elevation within a specific range is beneficial for the sensible and latent heat exchange of flue gas; The increase in steam content has a more positive impact on latent heat exchange. The most economically viable configuration emerges at Re=7 200 with 17% steam content, where the twisted honeycomb design demonstrates superior economic performance compared to conventional tubular condensers.This study serves as a valuable reference for designing and optimizing deep waste heat recovery systems for flue gas in natural gas heat treatment furnaces.