Abstract: Flatness control technology for cold-rolled strip is one of the core control technologies in the iron and steel industry. Its control effectiveness directly determines the post-rolling flatness quality and influences subsequent downstream processes. Flatness actuators are the key technological means for achieving flatness control. Lower accuracy in the actuator models can impair the online correction capability for flatness deviations and easily lead to flatness defects. This paper comprehensively considers the influence patterns of key rolling parameters, such as rolling force and strip geometric dimensions, on strip flatness, as well as the coupling mechanisms among different flatness actuators. Based on this, a roll bending-roll tilting coordinated setup model incorporating quadratic influence coefficients is established. The concept of an "overspray coefficient" is introduced to construct a segmented cooling flow control model that accounts for the partial flow overlap characteristics between adjacent emulsion nozzles. To enhance the accuracy and computational efficiency of the setup model, an optimization strategy for setting the coefficients in the setup model is developed based on heuristic search theory. Industrial trials are conducted using a 1 450 mm UCM five-stand six-high tandem cold rolling mill as the application platform. The results indicate that the flatness actuator setup model and strategy developed in this paper can efficiently and accurately correct online flatness deviations. They reduce the setup complexity of the model and improve the hit rate of flatness root mean square error by approximately 8%.